Masonry Design Guide - Boral

BORAL MASONRY
Build something great
Masonry Design Guide
SEGMENTAL BLOCK RETAINING WALLS QUEENSLAND BOOK 4
www.boral.com.au/masonry Updated July 2008

Queensland Book 4 A
A Introduction
Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A2
Fast Find Product and Application Guide . . . . . . . . . . . . . . . A3
B Planning and Design
C Gardenwall ®
Gardenwall Product Information . . . . . . . . . . . . . . . . . . . . . . C2
Selection and Construction Guidelines . . . . . . . . . . . . . . . . . C3
D Heathstone ®
Heathstone Product Information . . . . . . . . . . . . . . . . . . . . . . D2
Gravel-Fill Construction Guidelines . . . . . . . . . . . . . . . . . . . . D3
Curved Wall Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . D4
Step Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D5
E Keystone ® and Pyrmont ®
Keystone Product Information . . . . . . . . . . . . . . . . . . . . . . . E4
Pyrmont Product Information . . . . . . . . . . . . . . . . . . . . . . . . E5
Gravel-Fill Wall Selection and Construction Guidelines . . . . . E6
Typical Installation Details . . . . . . . . . . . . . . . . . . . . . . . . . . . E8
F Custom Engineered Walls
Engineered Retaining Walls . . . . . . . . . . . . . . . . . . . . . . . . . F2
Keysteel Product Information . . . . . . . . . . . . . . . . . . . . . . . . F4
Typical Soil-Anchor Application . . . . . . . . . . . . . . . . . . . . . . . F6
Typical Rock-Anchor Application . . . . . . . . . . . . . . . . . . . . . . F7
Typical Seawall Application . . . . . . . . . . . . . . . . . . . . . . . . . . F8
PAGE
An Introduction to
Segmental Block Retaining Walls . . . . . . . . . . . . . . . . . . . . . B2
Products @ a Glance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A4
About This Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A6
Site Investigation — Preliminary Design . . . . . . . . . . . . . . . . B6
Curved Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C4
Step Tread and Cap Unit Installation . . . . . . . . . . . . . . . . . . . D5
Corner Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6
No-Fines Concrete Wall Construction . . . . . . . . . . . . . . . . . . D7
No-Fines Concrete Wall
Construction Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . E11
Geogrid Soil-Reinforced
Wall Construction Guidelines . . . . . . . . . . . . . . . . . . . . . . . E13
Typical Specification for
Keystone/Pyrmont Retaining Walls . . . . . . . . . . . . . . . . . . . E15
Typical Terraced Wall Application . . . . . . . . . . . . . . . . . . . . . F9
Typical Fencing Application . . . . . . . . . . . . . . . . . . . . . . . . . F10
Typical Railing and Barrier Application. . . . . . . . . . . . . . . . . F11
The information presented herein is supplied in good faith and to the best of our knowledge was accurate at the time of preparation. No responsibility can be accepted by
Boral or its staff for any errors or omissions. Users are advised to make their own determination as to the suitability of this information in relation to their particular purpose
and specific circumstances. Since the information contained in this document may be applied under conditions beyond our control, no responsibility can be accepted by us
for any loss or damage caused by any person acting or refraining from action as a result of this information.
A2 July 2008 | BORAL MASONRY DESIGN GUIDE
PAGE

The quickest way to find a Boral Masonry Segmental Block Retaining Wall Solution.
Simply follow the FAST FIND guide on the right hand side of the table.
BORAL
MASONRY
SEGMENTAL
BLOCK
RETAINING
WALLS PRODUCT
Surcharge
Loading
Nil
� 5kPa
� 5kPa
or
� 1:4
Sloped
Backfill
� 25kPa
> 25kPa
Wall Height
(mm)
� 1000
� 1600
� 3000
> 3000
> 6000
Wall
Type
Vertical
Set Back
Vertical
Set Back
Property
Boundary
Not
Boundary
Vertical
Set Back
Vertical
Set Back
For technical support and sales office details please refer to the outside back cover
BORAL MASONRY DESIGN GUIDE | July 2008
Gardenwall
Heathstone
Pyrmont
Keystone
Keysteel
D E E ✱
C E ✱
D ✤ E ✤ E ✤ ✱
E ✤ ✱
Queensland Book 4 A
Core Filled Block
Max. wall heights disclaimer:
The gravity wall heights are maximum heights calculated in accordance with CMAA MA-53 Appendix D guidelines and a qualified engineer should confirm the suitability of the product
for each intended application. As such, due consideration must be given to but not limited to:
Cohesion,
Dry backfill: no ingress of any water into the soil behind the retaining wall,
All retaining walls are designed for zero surcharge.
These walls are intended for structure Classification A walls only as defined in AS4678 Earth Retaining Structures as being where failure would result in minimal damage and loss of access.
✱
E ★ E ★ ✱
E ★
E★ E★ F
F
1
2
✤
★
✱
Fast Find
a Boral
Solution
Select your application
criteria from the left
hand columns
Go straight to the book
section indicated by the
letter at the intersection of
application rows and
product columns (e.g.
Section E in this example)
Requires ‘No-fines Concrete
Backfill ’ or ‘Geogrid’ systems
Requiring ‘Geogrid’ systems
Please refer to Book 1, Boral
Masonry Design Guide and Book 2,
Boral Masonry Blocks & Bricks Guide
A3

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A
Landscape
Retaining Wall Systems
for low-height domestic and commercial
garden beds and retaining wall applications
• Gardenwall ®
Boral Gardenwall is ideal for gravity wall installations
of less than 1000mm wall height. The blocks are laid
with a slight set-back, and are located by a lug along
the back edge. Gardenwall can also be used curved
wall applications.
Heathstone ® and Heathstone ® Grand
Boral Heathstone retaining wall systems combine
the attractive impression of natural hewn stone,
the elegance of a vertical wall and the simplicity of
mortarless installation. Various installation formats
cater for walls up to 0.97m height. Heathstone Grand
double-length blocks are particularly effective in larger
installations.
A4 July 2008 | BORAL MASONRY DESIGN GUIDE

Engineered
Retaining Wall Systems
for domestic and commercial landscaping, roadside
and custom engineered retaining wall applications
Keystone ®
Boral Keystone walls have been proven time-andtime-again,
by engineers, architects, councils, road
authorities and landscapers throughout Australia.
Keystone walls can cater for a wide range of
applications from low height gravity walls to geogrid
soil reinforced applications up to 12m wall height.
Keystone walls can be constructed as near vertical
with curves as tight as 1m radius, or set-back.
Blocks are available in a wide selection of colours
and in two splitface formats:- standard (curved) and
flushface (straight).
BORAL MASONRY DESIGN GUIDE | July 2008
Queensland Que Qu Q eeens
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Book
k 4
A
Pyrmont ®
Boral Pyrmont retaining walls are a modern-day link
to our pioneer heritage. Pyrmont combines modern
engineering versatility with the elegance of a vertical
wall and the style of hand-finished natural stone.
Pyrmont gravity or soil reinforced retaining wall
systems can be engineered for applications up to 6m
height and can accommodate gentle curves and step
installations.
Keysteel Custom Engineered Retaining
Wall Systems
Boral Keysteel is a high performance engineered
retaining wall system for applications requiring wall
heights in excess of 6m and/or where critical surcharge
loadings are present. Boral Keysteel is an internationally
proven system that integrates the superior strength
and durability of Keysteel blocks with steel-ladder soilreinforcement
to provide engineered solutions for the
most demanding retaining structures.
A5

Queensland Book 4 A
Boral Masonry Product Range
Boral Masonry offers a comprehensive range of proven products
and systems including Segmental Block Retaining Wall
Systems, Segmental Paving Products, Masonry Blocks, Masonry
Bricks, Masonry Fire and Acoustic Wall Systems.
What’s in this Guide
The Boral Masonry Segmental Block Retaining Walls Guide,
(this book), details a comprehensive selection of retaining wall
options ranging from low height gravity landscaping walls to
critically loaded reinforced-soil retaining structures.
This guide has been prepared as a comprehensive Boral
Product Reference Guide. It does not attempt to cover all
the requirements of the Codes and Standards which apply
to retaining wall construction. All structural detailing should
be checked and approved by a structural engineer before
construction. Boral reserves the right to change the contents
of this guide without notice.
A Guided Tour of a Typical Product Information Page
Product pages are laid out in a consistent manner to assist with easy selection and specification
of Boral Masonry products.
Product Icons with
dimensions for
products available
in your region/
state
Colour and
Availability
information
for products
distributed in
your region/
state
Lifting
Bars
315
315
200
200
Pyrmont ® Pyrmont ®
Keystone ® & Pyrmont ®
A6 July 2008 | BORAL MASONRY DESIGN GUIDE
BOOK
4
PAGE
v1QLD Draft 02/02/05
E5
Vertical Retaining Wall System
455
455
INTRODUCTION
DESIGN CONSIDERATIONS
Standard Unit
Standard Unit
Boral Pyrmont retaining retaining wall systems wall Suitable Suitable for curved for wall curved wall
systems integrate integrate the engineering the engineering capabilities installations with with a suggested a suggested
355
355
355
355
capabilities of the Keystone of the system Keystone with system the minimum minimum convex convex curve curve radius radius of
with versatility the versatility and pleasing and aesthetics pleasing of of 5m (resulting in a 5mm lip).
455
455
Premium
Premium
Cap
Cap
Rockfaced
Rockfaced
65
65
65
65
355
355
Premium
Premium
Corner
Corner
Cap
Cap
Rockfaced
Rockfaced
200
200
aesthetics a vertical wall. of a The vertical Pyrmont wall. unit The is a COLOURS
COLOURS
Pyrmont split-face block unit is with a split-face four chamfered block Please refer to colour swatch
Please refer to colour swatch
with edges, emulating four chamfered the care, skill edges, and information for an indication of
information for an indication of
emulating determination the of stone care, masons skill from and current colours.
current colours.
determination Australia’s early of stone settler masons period. from
To reduce the possibility of staining
Australia s early settler period. To reduce the possibility of staining
Boral Pyrmont retaining wall system and to enable easier cleaning, a
and to enable easier cleaning, a
Boral is also Pyrmont suitable for retaining constructing wall system steps, masonry sealer can be applied to all
masonry sealer can be applied to all
is planter also suitable boxes, for gently constructing curved steps, walls visible surfaces after installation.
visible surfaces after installation.
planter and crisp boxes, 90° corners. gently curved walls
and crisp 90¡ corners.
227
227 455 455
455 455
90¡
90°
Corner
Corner
Unit
Unit
Right
Right
or
Left
Left
Hand
Hand
227
227
Keygrid Geogrid Geogrid Soil Soil Reinforcement
Reinforcement
Availability & and Colours Colours
•
No
No
minimum
minimum
order
order
quantities
quantities
apply.
apply.
•
Lead
Lead
time
time
0-4
0-4
weeks.
weeks.
•
Colour
Colour
swatch
swatch
is
is
a
a
guide
guide
only.
only.
Contact
Contact
your
your
nearest
nearest
Boral
Boral
Masonry
Masonry
sales
sales
office
office
for
for
a
a
sample.
sample.
Hawkesbury Yellow Yellow
Pins
BORAL MASONRY DESIGN GUIDE | July 2008
Please note that this guide is based on products available at the
time of publication from the Boral Masonry Queensland sales
region. Different products and specifications may apply to Boral
products sourced from other regions.
Specifications
Specifications
Additional Assistance and Information
• Contact Details: Please refer to the outside back cover of
this publication for Boral Masonry contact details.
• Colour and Texture Variation: The supply of raw
materials can vary over time. In addition, variation can
occur between product types and production batches. Also
please recognise that the printed colours in this brochure
are only a guide. Please, always ask to see a sample of your
colour/texture choice before specifying or ordering.
• Terms and Conditions of Sale: For a full set of Terms
and Conditions of Sale please contact your nearest Boral
Masonry sales office.
Queensland Book 4 E
Description HxLxDmm Wt kg N°/m2
Standard Unit
Description
Premium Cap (Rockfaced 1 side)
Standard Unit
Premium Corner Cap
Premium Cap (Rockfaced 1 side)
(Rockfaced 2 sides)
200x455x315 38.5 11
HxLxDmm Wt kg N…/m2
65x455x355 21.5 2.2/lin mtr
200x455x315 38.5 11
65x355x355 18.8 1/90° corner
65x455x355 21.5 2.2/lin mtr
Premium Corner Cap 65x355x355 18.8 1/90¡ corner
90° Corner Unit (Right or Left Hand) 200x455x227 28.8 5/vertical metre
(Rockfaced 2 sides)
Pins 2 pins per full unit
90¡ Corner Unit (Right or Left Hand) 200x455x227 28.8 5/vertical metre
(high strength pultruded fibreglass)
Pins
Lifting Bars
2 pins per full unit
(Pyrmont units should be lifted by
(high strength pultruded fibreglass)
two people using the Keystone lifting bars)
Lifting Bars (Pyrmont units should be lifted by
two people using the Keystone lifting bars)
E5
Product Range, Book and
Page Identification
Product Name and other
identifying features
Product information
relating to features,
applications, and
accessories
Product Specifications

BORAL MASONRY
Build something great
Masonry Design Guide
SEGMENTAL BLOCK RETAINING WALLS QUEENSLAND BOOK 4
B PLANNING AND DESIGN
44B

Queensland Book 4 B
An Introduction to Segmental
Block Retaining Walls
Background
For many years cantilever retaining walls have been constructed
with reinforced concrete masonry stems (steel reinforcement
grouted into hollow concrete block work) and reinforced
concrete footings. (Refer to Fig B1).
Segmental block gravity retaining structures, consisting
of dry-stacked concrete units which resist overturning by
virtue of their own weight and setback, were introduced into
Australia in the early 1990’s, and rapidly became popular. This
system provides an attractive and cost effective solution, but
its stability is limited by the geometry of the units and wall
heights. (Refer to Fig B2).
In order to achieve greater heights, reinforced-soil walls (such
as Boral Keystone) were introduced. These walls typically
consist of geosynthetic materials, which are placed in
horizontal layers in the compacted backfill and mechanically
connected to the blocks. Such systems can be constructed
several metres high, and accommodate significant loads.
A further development of this system is the Boral Keysteel
system which utilises steel-ladder reinforcement. Here the
steel-ladder reinforcement is placed in horizontal layers in
the compacted backfill and mechanically connected to the
blocks. These systems are individually engineer designed,
and are suitable for walls in excess of 6m high and for critical
surcharge loadings. (Refer to Fig B3).
B2
Steel reinforced
and concrete
grout filled
hollow concrete
block wall
Fig B1 — Typical Reinforced Concrete Masonry
Cantilever Retaining Wall
Reinforced
concrete
footings
Segmental block gravity
retaining structure, drystacked
against a soil
slope
Fig B2 — Typical Segmental Block
Gravity Retaining Wall
Fig B3 — Typical Reinforced-Soil
Segmental Block Retaining Wall
Segmental
concrete
gravity
retaining
structure, with
reinforced soil
July 2008 | BORAL MASONRY DESIGN GUIDE

Behaviour of Segmental Block
Reinforced-Soil Retaining Walls
If unrestrained, a soil embankment will slump to its angle
of repose. Some soils, such as clays, have cohesion that enables
vertical and near-vertical faces to remain partially intact, but
even these may slump under the softening influence of ground
water. When an earth retaining structure is constructed, it
restricts this slumping. The soil exerts an active pressure on
the structure, which deflects a little and is then restrained
by the friction and adhesion between the base and soil
beneath, passive soil pressures in front of the structure and
bearing capacity of the soil beneath the toe of the structure.
If water is trapped behind the retaining structure, it exerts
an additional hydraulic pressure. This ground water also reduces
the adhesion and bearing resistance.
If massive rock formations are present immediately behind the
structure, these will restrict the volume of soil which can be
mobilised and thus reduce the pressure.
Reinforced-soil systems consist of a series of horizontal
geogrids that have been positioned and pulled tight within
a compacted soil mass, thus strengthening it and restricting its
slump. The geogrids are strategically placed to intersect potential
failure planes that are inclined from near the base of the wall,
up at an angle (depending on the soil properties), to the top of
the fill. The function of the geogrids is to ‘strengthen’ the soil
mass and they are ‘anchored’ by compacted backfill beyond the
potential failure planes.
Local collapse and erosion of the front face is eliminated by
fixing concrete segmental facing units to the exposed ends
of the geogrids. However, the segmental concrete facing is
not designed to ‘retain’ the strengthened soil mass, which
should be able to stand independently of the facing except
for local effects. The connection spacing (and the geogrid
spacing) must account for the local stability of the facing,
including bulging and rotation above the top geogrid. The
top capping course is normally bonded to the course below
using a concrete to concrete adhesive.
A surface sealing layer and surface drainage system minimise
the quantity of rainwater entering the soil mass. A sub-surface
drainage system behind the segmental concrete facing and
(sometimes) beneath the wall reduce pore water pressures and
thus reduce the tendency for local or global slip.
Thus, the essential features of a properly designed and constructed
segmental block reinforced soil retaining wall are:
• Geogrids with adequate length and strength;
BORAL MASONRY DESIGN GUIDE | July 2008
Queensland Book 4 B
• Adequate connection to the facing to provide local
stability;
• A drainage system that will relieve hydro static pressures
for the life of the structure.
Importance of a Geotechnical Report
The design of a reinforced soil retaining wall includes two
essential parts:
• Analysis of the proposed reinforced soil structure and
the adjacent ground for global slip, settlement, drainage
and similar global considerations; and
• Analysis and design of the reinforced soil structure itself.
These analyses must be based on an accurate and complete
knowledge of the soil properties, slope stability, potential slip
problems and ground water.
Except in the case of simple structures, a geotechnical report
by a qualified and experienced geotechnical engineer should
be obtained.
Such a report must address the following considerations, as well
as any other pertinent points not listed.
• Soil properties;
• Extent and quality of any rock, including floaters and
bedrock;
• Global slip and other stability problems;
• Bedding plane slope, particularly if they slope towards
the cut;
• Effect of prolonged wet weather and the consequence of
the excavation remaining open for extended periods;
• Effect of ground water;
• Steep back slopes and the effect of terracing;
• Effect of any structures founded within zone of influence.
Safety and Protection of Existing
Structures
Whenever soil is excavated or embankments are constructed,
there is a danger of collapse. This may occur through
movement of the soil and any associated structures by:
• Rotation around an external failure plane that encompasses
the structure;
• Slipping down an inclined plane;
• Sliding forward, or
• Local bearing failure or settlement.
B3

Queensland Book 4 B
These problems may be exacerbated by the intrusion of surface
water or disruption of the water table, which increase pore water
pressures and thus diminish the soil’s ability to stand without
collapse.
The safety of workers and protection of existing structures
during construction must be of prime concern and should
be considered by both designers and installers. All excavations
should be carried out in a safe manner and in accordance with
the relevant regulations, to prevent collapse that may endanger
life or property. Adjacent structures must be founded either
beyond or below the zone of influence of the excavation. Where
there is risk of global slip, for example around a slip plane
encompassing the proposed retaining wall or other structures,
or where there is risk of inundation by ground water or surface
water, construction should not proceed until the advice of a
qualified and experienced Geotechnical Engineer has been
obtained and remedial action has been carried out.
Global slip failure
Soil retaining structures must be checked for global slip failure
around all potential slip surfaces or circles.
Designers often reduce the heights of retaining walls by splitting
a single wall into two (or more) walls, thus terracing the site.
Whilst this may assist in the design of the individual walls, it will
not necessarily reduce the tendency for global slip failure around
surfaces encompassing all or some of the retaining walls.
Analysis for global slip is not included in this guide, but it is
recommended that designers carry out a separate check using
commercially available software.
Differential Settlement
The Concrete Masonry Association of Australia (CMAA)
recommends that for dry stacked mortarless retaining walls
employing masonry units (i.e. units with an area less
than 0.2m2) on an aggregate levelling pad, the differential
settlement should be limited to 1% of the length. Whilst it
is permissible for the retaining wall to undergo differential
settlement up to 1% of the length, it may be preferable
to limit settlement to a lower figure giving consideration
to aesthetics (i.e. keeping the bedding planes level), in
addition to the structural considerations.
Techniques to reduce or control the effects of differential
settlement include:
B4
• Articulation of the wall (in discontinuing the normal
stretcher bond) at convenient intervals along the length,
or
• Excavating, replacing and compacting areas of soft soil,
• Limiting the stepping of the foundation and bottom course
to a maximum 200mm.
Unit Cracking/Gapping — Settlement
Keystone modular retaining wall structures can tolerate a certain
amount of settlement due to the flexible nature of the system
and small individual unit size.
Observation of a number of completed structures that have
undergone settlement indicates that the wall’s tolerance for
settlement without cracking is inversely proportional to the wall
height. Lower height walls (H5m). This increased
flexibility is due to lower confining forces and load transfer taking
place on each block, which permits small individual movements
to occur, accommodating the settlement experienced without
facial distress. Taller walls place the lower wall units under
considerable confining pressure, restricting unit movement and
permitting shear and flexural stresses to build up to the point
where a block cracks as a means of stress relief.
Low wall settlement problems are typically observed in residential
projects where soils adjacent to houses are uncompacted and
the walls settle differentially over a short distance. Usually
gapping or offset joints are visually noted and the settlement
is obvious.
Gapping and offset joints
Fig B4 — Typical Low Wall
Settlement
Downward
movement
July 2008 | BORAL MASONRY DESIGN GUIDE

Tall wall settlement is not as obvious but occasional facial
cracks can be observed in areas of flexural stress concentration,
typically in small groupings in the bottom 1/3 of the wall.
Settlement induced cracks are usually not structurally
significant and are just a means of facial stress relief for the
unreinforced dry-stack facing system. However, cracked units
can be a symptom of other types of problems, so a review by
an engineer is always recommended.
High confining
pressure
Flexural stress
Facial cracks
Importance of Drainage
Downward
movement
Fig B5 — Typical Tall Wall
Settlement
This guide assumes that a properly functioning drainage system
is effective in removing hydraulic pressure. If this is not the
case, the designer will be required to design for an appropriate
hydraulic load.
Based on an effective drainage system, it is common to use
drained soil properties. For other situations, the designer
must determine whether drained or undrained properties are
appropriate. In particular, seawalls that may be subject to rapid
drawdown (not covered in this guide) require design using
undrained soil properties.
BORAL MASONRY DESIGN GUIDE | July 2008
Queensland Book 4 B
B5

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B
Site Investigation: Preliminary Design
Client: __________________________________________________________________________
Project: _________________________________________________________________________
Location: ________________________________________________________________________
Use for which retaining wall is intended: _____________________________________________
Proximity of other structures to the face of the retaining wall:
B6
Date: _______________________
Report prepared by: _______________________
Structure or load Distance (m)
Distance of live loads from top of wall (Dqi) _______________________
Distance of dead loads from top of wall (Dqd) _______________________
Distance of point loads from top of wall (Di) _______________________
Distance of other structures from base of wall (Ds) _______________________
Structure classification: _________________________________________________
For guidance refer AS4678, Table 1.1
Structure Classification Examples
2. Where failure would result in significant damage or risk to life
3. Where failure would result in moderate damage and loss of services
4. Where failure would result in minimal damage and loss of access
Required design life: _____________________________________________________
For guidance refer AS4678, Table 3.1
Type of Structure Design life (years) Type of Structure Design life (years)
Temporary site works 5 Residential dwellings 60
Mine structures 10 Minor public works 90
Industrial structures 30 Major public works 120
River and marine structures 60
Wall geometry:
Wall height above GL (H’)
Embedment depth (Hemb)
___________ m
H/20 or 200mm ___________ m
Wall slope (v) ___________ °
Angle of backfill slope (b) ___________ °
Height of backfill (h)
Foundation material:
Allowable bearing pressure
___________ m
Under reinforced soil block ___________ kPa
Water profile:
Water table depth within wall fill ___________ m
Retained soil data:
Soil density (g r ) ___________ kN/m 3
Internal friction angle (fr ) peak ___________ °
Cohesion (C* i ) ___________ kPa
Loading data:
Dead load surcharge (qd ) ___________ kPa
Live load surcharge (ql ) ___________ kPa
Horizontal line load (F) ___________ kN/m
Vertical line load (P) ___________ m
Width of bearing (b) ___________ m
July 2008 | BORAL MASONRY DESIGN GUIDE

BORAL MASONRY
Build something great
Masonry Design Guide
SEGMENTAL BLOCK RETAINING WALLS QUEENSLAND BOOK 4
C GARDENWALL ®
44C

Queensland Book 4 C
C2
295
Availability and Colours
• No minimum order quantities apply.
• Lead time 0-2 weeks.
• Colour swatches are a guide only. Contact your
nearest Boral Masonry sales office for a sample.
Kota Green
Paperbark
203
125
Standard Unit
295
Light Sands Terrain
Specifications
203
Portstone
125
Soft Split Unit
Charcoal
Terracotta Sunset
Gardenwall ®
Retaining Wall System
INTRODUCTION
Boral Gardenwall is ideal for low
landscaping walls and edgings
in garden and communal areas.
Gardenwall’s rockface texture, multifaceted
face and setback construction
produces an aesthetically pleasing
feature for landscaped areas.
Gardenwall is often used for garden
edges and raised beds, terraces and
to create decorative features such as
around pools.
DESIGN CONSIDERATIONS
Depending on the foundation
and retained soil characteristics,
Gardenwall is effective as a gravity
retaining wall structure up to
1000mm (maximum 8 courses).
Never install where loads (e.g.
buildings, driveways) will be located
within 1000mm of the wall. For
engineered walls (to AS4678) higher
than 1000mm, or where a surcharge
is present, Boral Keystone or
Pyrmont walls should be considered.
ADVANTAGES
• Gardenwall does not require
concrete foundations.
• Easy installation of straight walls
and curved walls.
• Durable, low maintenance, longterm
landscaping.
• Solid units — eliminates the need
for capping and corner units.
COLOURS
Gardenwall is offered in a range
of colours to suit traditional and
contemporary settings. Please refer
to colour swatch information for an
indication of current colours.
To reduce the possibility of staining
and to enable easier cleaning, a
masonry sealer can be applied to all
visible surfaces after installation.
Product Description Finish HxLxDmm Approx Wt kg No. per m2
Standard Unit Rockfaced 125x295x203 13.2 26.9
Soft Split Rockfaced 125x295x203 14.95 26.9
July 2008 | BORAL MASONRY DESIGN GUIDE

Selection and Construction Guidelines
IMPORTANT: Please consult with the regulating council for
local design requirements prior to the design and construction
of a retaining wall. Councils in general require that retaining
walls be designed and certified by a suitably qualified engineer
where the wall is over 0.5m in height and/or where there is
surcharge loading such as a roadway, house, or other structure
near the wall.
• Boral Gardenwall is only suitable for walls up to 1000mm
in height and where no loads or surcharge exists within
1000mm behind the wall.
Installation
• Remove the retaining lug on the base of the unit on those
Gardenwall blocks being used in the base course only (this
makes levelling the first course much easier). To remove
the lip, place at an angle on the ground and strike the lug
firmly with a hammer. (Safety glasses should be worn).
• As a safety precaution to avoid lifting or movement of the
top units, it is recommended that the top course units
are secured using a construction adhesive. This is also
recommended in areas of possible vandalism.
• Standard units can also be used to construct convex
curves.
No loads to be located within 1000mm behind wall
Backfill should be no higher than the top of the wall
Native soi l
BORAL MASONRY DESIGN GUIDE | July 2008
350mm
min.
Dish drain to direct surface
run-off (if required )
Filter fabric to keep dirt
out of drainage layer
1
5
10 0mm min .
Queensland Book 4 C
Retaining Soil Type
Wall Height
H (mm)
POOR Clay, Silt, Fine sand 750
AVERAGE Coarse sand 875
GOOD Gravel, Stone 1000
Gardenw all Uni t
Backfill placed and
compacted in 250mm laye rs
300mm width of 12-20mm
free draining granular
material eg. blue metal
Drainage pipe
First cou rse to be buried below
final ground level (to engineer's
specification - 10 0mm min. )
Compacted road base levelling
pad on undisturbed inor ganic soil
Fig C1 — Typical Gravity Wall Construction Detail — Gardenwall
Note: Refer to max. wall heights disclaimer on page A3 of this guide.
The gravity wall heights are maximum heights calculated in accordance with CMAA MA-53 Appendix D guidelines and a qualified engineer should confirm
the suitability of the product for each intended application.
H
C3

Queensland Book 4 C
Curved Walls
C4
Minimum Radius = 666mm for top course
For base course radius add 43mm
for each course below
Fig C2 — Construction of Curved Walls
• When designing Gardenwall for convex curves to the
maximum height of 8 courses, it is necessary to begin
with a minimum radius of 1000mm. It may also be
necessary to remove the outer portions of the retaining
lug from each unit to maintain a consistent setback. It is
important that the entire lug is not removed.
• When building curves, some blocks may also require
trimming of the length to maintain a half bond pattern.
July 2008 | BORAL MASONRY DESIGN GUIDE

BORAL MASONRY
Build something great
Masonry Design Guide
SEGMENTAL BLOCK RETAINING WALLS QUEENSLAND BOOK 4
D HEATHSTONE ®
44D

Queensland Book 4 D
Grand Unit
D2
280
440
440
162
220
Standard Unit
Classic Unicap
280
280
162
65
380
Availability and Colours
• No minimum order quantities apply.
• Lead time 0-2 weeks.
Portstone
300
Rockface
Corner Cap
270
300
50
162
Standard Corner Unit
Single Sided
Rockface Cap
Light Sands
600
Colour swatches are a guide only. Contact your nearest
Boral Masonry sales office for a sample.
300
Heathstone ®
Retaining Wall System
INTRODUCTION
Boral Heathstone is ideal for low,
vertical landscaping walls in garden
and communal areas. The rockface
texture and bevelled edges add
a formal and elegant element to a
landscaped area. Heathstone is
often used to separate and highlight
entertaining areas, BBQ areas, paths,
garden beds, hedges, or to create and
differentiate levels. Heathstone is
also suitable for constructing steps,
planter boxes and for curved walls.
DESIGN CONSIDERATIONS
Depending on the foundation
and retained soil characteristics,
Heathstone is effective as a gravity
structure up to 972mm, or up to
1600mm when installed with nofines
concrete backfill. Heathstone
should not be used where the base soil
or backfill is not firm, or is of expansive
clay. Never install where loads (e.g.
buildings, driveways) will be located
within 1000mm of the wall. For walls
higher than this, or where a surcharge
is present, Boral Keystone or Pyrmont
walls should be considered.
Specifications
The range of Heathstone components
is designed to optimise space, and
includes a ready-to-install corner
unit and a series of caps to
accommodate single or double sided
applications.
COLOURS
Heathstone is offered in colours
which emulate natural hewn stone,
and which contrast beautifully with
soil, mulch, shrubbery and grassed
areas. Please refer to colour swatch
information for an indication of
current colours.
To reduce the possibility of staining
and to enable easier cleaning, a
masonry sealer can be applied to all
visible surfaces after installation.
Product Description Finish HxLxDmm Approx Wt kg No. per m2
Standard Unit Rockfaced 162x220x280 12.1 28.1 units/m2
Standard Corner Unit Rockfaced x 2 Faces 162x380x280 26.3 1/course/corner
Classic Cap Rockfaced x 1 Face 65x440x280 2.2/linear metre
Grand Unit Rockfaced 162x440x280 26.5 14.05 units/m2
Single Sided Rockface Cap Rockfaced 50x600x300 20.4 1.6/linear metre
Double Sided Rockface Cap Rockfaced x 2 Long Edges 50x600x300 20.3 1.6/linear metre
Rockface Corner Cap Rockfaced x 2 Adjacent Edges 50x300x300 10.5 1/corner
Note: Refer to max. wall heights disclaimer on page A3 of this guide.
50
Double Sided Rockface Cap
600
300
50
July 2008 | BORAL MASONRY DESIGN GUIDE

Heathstone ® Gravel-Fill Construction
IMPORTANT: Please consult with
the regulating council for local design
requirements prior to the design and
construction of a retaining wall. Councils
in general require that retaining walls
be designed and certified by a suitably
qualified engineer where the wall is over
0.5m in height and/or where there is
surcharge loading such as a roadway,
house, or other structure near the wall.
150mm min. of 12-20mmØ
free draining granular
material eg. blue metal
No loads to be located
within 1.0m of the wall
Native soil
Compacted
roadbase
BORAL MASONRY DESIGN GUIDE | July 2008
350mm
min.
Dish drain to direct surface water
or filter fabric to stop silt filling
drainage layer
Voids in and around Heathstone
blocks to be filled (if required)
with 12-20mmØ free draining
granular material eg. blue metal
Backfill (eg. excavated soil)
to be placed and
compacted as each course
of blocks is laid
Agricultural drainage line 100mmØ
100mm min.
Blocks to be embedded
a minimum of 100mm
Fig D1 — Typical Construction Detail — Heathstone Gravel-Fill
Table D1 - Maximum Wall Height — Heathstone Gravel-Fill
Queensland Book 4 D
Refer to Heathstone
Gravel-Fill Selection
Table for maximum
number of courses
Maximum Courses Maximum Courses
For walls without gravel fills For walls with gravel fills
to all voids and cores to all voids and cores
Poor soils — including sands, gravelly
clays, sandy clays and silt clays 2 (324mm) 4 (648mm)
Average soils — including well graded
sands and gravelly sands 3 (486mm) 5 (810mm)
Good soils — including gravels, sandy
gravels and crushed sandstone 4 (648mm) 5 (810mm)
NOTES: Backfill retained by a retaining wall should be no higher than the top of the retaining wall.
For engineered retaining walls to AS4678, refer to the Heathstone No-Fines Concrete Wall Guidelines.
Refer to max. wall heights disclaimer on page A3 of this guide.
The gravity wall heights are maximum heights calculated in accordance with CMAA MA-53 Appendix D guidelines and a qualified engineer
should confirm the suitability of the product for each intended application.
D3

Queensland Book 4 D
Curved Wall Construction
using the Unicap
Curves as small as 1015mm in radius can be constructed with
Heathstone Standard Units.
NOTE: Unicap radius is 735mm to the inside face and 1015mm
to the outside face.
D4
735mm to face of
Heathstone in
concave curve
1015mm to the face
of Heathstone
in convex curve
350
35 35
280
Bolster back
of blocks to
form convex
curves
Fig D3 — Forming Convex Curve
Classic
Unicap
Fig D2(a) — Heathstone Curved Cap Radius to suit Unicaps
(Not suitable for Grand Units)
Convex (External) Curves - Applies to Double Sided
Rockface Caps Only.
• For convex curves, the tails of the blocks must be
trimmed to suit the desired radius. Use a hammer and
bolster on the back, top and bottom of the tail. Use light
hammer blows first to trace the area to be removed, then
a heavier blow on top. Repeat the tracing and final blow
if necessary.
NOTE: Unicaps will need
to be trimmed to suit
the curve
Concave (Internal) Curves - Applies to both Unicaps
or Double Sided Rockface Caps.
• For concave curves use Standard Units spaced evenly to
a scribed arc in conjunction with Double Sided Rockface
Curved Caps butted together to form a 1500mm radius
wall face.
Heathstone
Standard Unit
Concave Curve Radius
Fig D4 — Forming Concave Curve
NOTE: Premium Curved
Caps have an inside
radius of 1500mm
July 2008 | BORAL MASONRY DESIGN GUIDE

Step Construction
Applies to Double Sided Rockface Caps
and Classic Unicap.
45
162
Remove locating
lugs before laying
255
1:10
Cement : Sand
BORAL MASONRY DESIGN GUIDE | July 2008
25
Heathstone
Units
Double Sided
Rockface Cap
Fix cap units with
construction adhesive
Native soil
Fig D5 — Construction of Heathstone Steps
Queensland Book 4 D
Step Treads and Cap Unit Installation
• To allow for installation of the Double-sided Rockface Cap
units and step treads, it is necessary to bolster locating
lugs from the blocks.
• Push the Heathstone split-face into sand for support. Trace
along the back of the lug with a bolster and hammer,
increasing the force of hammer blows until the lug
splits off. All blows must be from the back of the block,
with the bolster blade nearly parallel to the top of the
Heathstone unit. Refer to the illustration. Any remaining
high spots should be removed with a scutch hammer or
an old screwdriver and hammer. (Safety glasses must be
worn).
Fig D6 — Bolstering Lug from Heathstone Units
D5

Queensland Book 4 D
Corner Construction
Constructing Internal and External Corners
• Corners are constructed using Corner Units and Standard
Units or Grand Units.
• Lay the Corner Units’ largest splitface in alternate
directions in adjacent courses (see illustrations).
D6
Corner Unit
Corner Unit
Fig D7 — Heathstone Standard External Corner (270°)
110mm
Standard Unit
Corner Unit
Corner Unit
Fig D8 — Heathstone Standard Internal Corner (90°)
• Continue this step until the desired height of the wall
is achieved.
• Use a construction adhesive to secure corner blocks
and caps.
Grand Unit
160mm
160mm
Bolster lug
to fit next
course
Cut from
Standard
Corner unit
onsite
Grand Unit
Fig D9 — Heathstone Grand External Corner (270°)
Grand Unit
Bolster lug to
fit next course
Grand Unit
NOTE: Internal 90º corners using Grand
Units do not require corner units
220mm
Bolster lug to
fit next course
Fig D10 — Heathstone Grand Internal Corner (90°)
July 2008 | BORAL MASONRY DESIGN GUIDE

Heathstone ® No-Fines Concrete Wall Construction
No-Fines Concrete shall consist of cement, water and coarse
aggregate. Cement will comply with the definitions for cement
per AS3972-1991 — ‘Portland and Blended Cements’. The
quantity of cement is specified as 210kg/m3 with a total
water/cement ratio of between 0.45 and 0.55.
The particle size distribution of the aggregate shall comply with
the limitations for the nominal single sized 20mm aggregate
specified in AS2758.1.
NOTES:
• Table D2 is based on AS4678 : 2002, Earth Retaining
Structures. The code assumes a surcharge of 5kPa is
applied to all retaining wall structures.
No loads above 5KPa to be
located within 1.0m of the wall
Retained soil
25MPa concrete
footing on 150kPa
allowable bearing
capacity material
f Denotes the internal angle of friction of the retained material
BORAL MASONRY DESIGN GUIDE | July 2008
T
600mm min.
Blocks to be embedded to
engineer‘s detail (1 course min.)
Queensland Book 4 D
• Global stability and all design considerations should be
checked by an engineer in poor clay conditions.
• Design assumes a dry excavation (i.e. water table is
below bottom of footing level). If ground water exists in
the excavation the wall is to be re-designed by a suitably
qualified engineer.
• These tables are supplied free of charge and do not form
any part of any contract with the user.
• 15MPa No-Fines concrete with a 6:1 ratio (Gravel :
Cement).
• Remove tail fins to allow “no fines” to connect block fill to
back fill.
Cap unit
Filter fabric or dish drain
15MPa ‘No Fines’ concrete.
All voids within and around
units to be completely filled.
Sub-soil drain connected
to stormwater system
or flood pit. Place loose
aggregate around subsoil
drain before pouring
no-fines concrete.
Pour no-fines concrete
directly onto prepared
foundation material
150mm min.
Fig D11 — Typical Construction Detail — Heathstone No-Fines Concrete Wall
Table D2 — Heathstone Maximum Wall Heights — No-Fines Concrete Construction
H
(Refer to Heathstone
No-Fines Concrete
Selection Table)
Wall Height Retained Soil Retained Soil Retained Soil
‘H’ (mm) CLAY f = 26° (POOR) SAND f = 30° (AVERAGE) GRAVEL f = 34° (GOOD)
‘T’ (mm) ‘T’ (mm) ‘T’ (mm)
972 670 570 570
1296 730 770 670
1620 1170 970 770
D7

Queensland Book 4 D
• The density of this product will vary with the density
of the aggregate used. The density range may be from
1650kg/m3 to 2100kg/m3.
• The void ratio of the mix is expected to be between 20%
and 30% and should be free draining.
• The compressive strength should generally exceed
10MPa for design purposes.
• This product has no slump and exerts similar pressures on
the soil and formwork, as does loosely poured aggregate.
No-Fines Construction Steps
Special purpose construction such as waterside walls, post
fixing, earthquake zones, and terraces will require additional
engineer’s design.
STEP 1:
Excavation/Preparation of Levelling Pad
Excavate a trench 600mm wide and sufficiently deep to allow a
150mm levelling base plus 1 course below ground.
D8
STEP 2:
Installing the First Course
Lay the first course of Heathstone units side by side over the
prepared base. Bolster off the tails so that ‘No-Fines’ concrete
connects backfill to core-fill areas.
STEP 3:
No-Fines Concrete Backfill
Backfill the first 2½ courses of the wall with ‘No Fines’ concrete.
All voids inside and between the units must also be filled. The
vertical height of any pour of ‘No Fines’ concrete is limited to
400mm. For walls greater in height, each pour must be allowed
to harden prior to pouring the next lift. Alternatively the wall may
be propped to support the lateral load from the wet concrete.
STEP 4:
Installing Capping Units
Install capping units and fix with construction adhesive.
July 2008 | BORAL MASONRY DESIGN GUIDE

BORAL MASONRY
Build something great
Masonry Design Guide
SEGMENTAL BLOCK RETAINING WALLS QUEENSLAND BOOK 4
E KEYSTONE ® AND PYRMONT ®
44E

Queensland Book 4 E
Keystone ® and Pyrmont Retaining Wall Systems
The Keystone Retaining Wall System is a world-wide
success story, and since its introduction by Boral into
Australia in 1992, hundreds of thousands of square
metres have been installed along our highways, roads
and transport corridors, and around our sports facilities,
buildings, foreshores and open spaces.
Boral Keystone retaining wall systems combine proven
engineering capabilities with design versatility, cost
effectiveness, lasting durability and an attractive dynamic
appearance to provide total solutions for retained earth
structures.
Keystone ®
Boral Keystone systems provide infinite flexibility
for design variation and individuality. The range of
components and installation methods cater for straight,
curved and terraced walls, level or stepped foundations
and capping, and a near vertical or set-back face. Then
there is a choice of standard or flushface, and a selection
of popular standard colours or custom colours can be
ordered for larger projects.
Pyrmont ®
Boral Pyrmont retaining wall system retains all of the
engineering characteristics of the Keystone system
and combines them with a more traditional appeal of a
bevelled-edge splitface block, and vertical construction to
emulate walls built during Australia’s pioneering era.
The range of components and installation methods
cater for straight and gently curved walls as well as
crisp 90º corners, while the rock-faced caps provide a
finishing touch that completes the transformation into a
masterpiece from the colonial era.
E2 July 2008 | BORAL MASONRY DESIGN GUIDE

Proven Engineering
Various installation methods cater for simple gravity walls
through to geogrid soil-reinforced retaining structures.
Boral Keystone and Pyrmont systems can also cater
for critical surcharge loads, enabling the construction
of buildings or roadways close to the wall to optimise
land usage.
For high performance retaining walls, please refer to the
section on Boral Keysteel Custom Engineered Retaining
Wall Systems later in this guide.
Durability
Boral Keystone and Pyrmont systems combine the
durability of concrete units and interlocking fibreglass pins
to produce maintenance free walls with life expectancies
of up to 120 years.
BORAL MASONRY DESIGN GUIDE | July 2008
Queensland Book 4 E
Ease of Construction
Boral Keystone and Pyrmont systems are designed to reduce
construction time and cater for all locations. The modular
blocks can be moved and installed without the need for
heavy lifting machinery, and the dry stacked, mortarless
installation provides less complex, more rapid construction.
E3

Queensland Book 4 E
455
Standard Cap
Lifting Bars
455
Standard Unit
315
275
200
100
484
Flushface Cap
Pins
485
Flushface Unit
Keygrid Geogrid Soil Reinforcement
315
275
Availability and Colours
• No minimum order quantities apply.
• Lead time 0-4 weeks.
• Colour swatches are a guide only. Contact your nearest
Boral Masonry sales office for a sample.
Charcoal Parchment
Terrain
Sunset
200
100
Keystone ®
Retaining Wall Systems
INTRODUCTION
Boral Keystone is an advanced, highly
versatile and thoroughly proven high
performance segmental block retaining
wall system which can be used as a
gravity structure or it can incorporate
geogrid soil-reinforcement to cater for
greater heights and surcharge loading
situations.
DESIGN CONSIDERATIONS
• Suitable for straight and curved
wall installations with a minimum
convex curve radius of 1800mm
without trimming the tail width,
or 970mm radius by trimming
the tail to 300mm width.
Specifications
• Can be installed as near vertical, or
for straight walls without curves
or corners it can be installed with
a 1-in-8 setback.
COLOURS
Keystone is offered in a range
of colours to suit decorative and
engineering applications. Please
refer to colour swatch information for
an indication of current colours.
To reduce the possibility of staining
and to enable easier cleaning, a
masonry sealer can be applied to all
visible surfaces after installation.
Description HxLxDmm Wt kg N°/m2
Standard Unit 200x455x315 32 11
Standard Cap 100x455x275 20 2.2/lin mtr
Flushface Unit 200x485x315 39 10.3
Flushface Cap 100x484x275 21 2.2/lin mtr
Pins 2 pins per full unit
Lifting Bars
(high strength pultruded fibreglass)
(Keystone units should be lifted by
two people using the Keystone lifting bars)
E4 July 2008 | BORAL MASONRY DESIGN GUIDE

Standard Unit
Premium Cap
Rockfaced
455
227
455 455
227
90° Corner Unit
Right or Left Hand
Lifting Bars
455
315
200
355
65
200
355
355
Premium Corner Cap
Rockfaced
Availability and Colours
• No minimum order quantities apply.
• Lead time 0-4 weeks.
• Colour swatch is a guide only. Contact your nearest Boral
Masonry sales office for a sample.
Hawkesbury Yellow
Pins
Keygrid Geogrid Soil Reinforcement
BORAL MASONRY DESIGN GUIDE | July 2008
65
INTRODUCTION
Boral Pyrmont retaining wall systems
integrate the engineering capabilities
of the Keystone system with the
versatility and pleasing aesthetics of
a vertical wall. The Pyrmont unit is a
split-face block with four chamfered
edges, emulating the care, skill and
determination of stone masons from
Australia’s early settler period.
Boral Pyrmont retaining wall system
is also suitable for constructing steps,
planter boxes, gently curved walls
and crisp 90° corners.
Specifications
Queensland Book 4 E
Pyrmont ®
Vertical Retaining Wall System
DESIGN CONSIDERATIONS
Suitable for curved wall
installations with a suggested
minimum convex curve radius
of 5m (resulting in a 5mm lip).
COLOURS
Please refer to colour swatch
information for an indication of
current colours.
To reduce the possibility of staining
and to enable easier cleaning, a
masonry sealer can be applied to all
visible surfaces after installation.
Description HxLxDmm Wt kg N°/m2
Standard Unit 200x455x315 38.5 11
Premium Cap (Rockfaced 1 side) 65x455x355 21.5 2.2/lin mtr
Premium Corner Cap
(Rockfaced 2 sides)
65x355x355 18.8 1/90° corner
90° Corner Unit (Right or Left Hand) 200x455x227 28.8 5/vertical metre
Pins 2 pins per full unit
(high strength pultruded fibreglass)
Lifting Bars (Pyrmont units should be lifted by
two people using the Keystone lifting bars)
E5

Queensland Book 4 E
Gravel-Fill Wall Selection
For low, non-critical walls, (i.e.. walls covered in the adjacent
table) the Keystone and Pyrmont Retaining Wall Systems are
effective as a gravity wall structure, utilising their weight and
interaction of the units to resist earth pressures.
Retained Soil Descriptions
Poor Soils Include fine sands, gravelly
clays, sandy clays, silty sands.
Angle of internal friction � 25°
Average Soils Include well graded sands,
gravelly sands.
Angle of internal friction � 30°
Good Soils Include gravels, sandy gravels,
crushed sandstone
Angle of internal friction � 35°
NOTES: Pyrmont walls can only be constructed in near vertical
format, and must be selected on the basis of data in the near
vertical column from Table E1.
Table E1: Refer to max. wall heights disclaimer on page A3 of
this guide. The gravity wall heights are maximum heights
calculated in accordance with CMAA MA-53 Appendix D
guidelines and a qualified engineer should confirm the
suitability of the product for each intended application.
Gravel-Fill Wall Construction Guidelines
IMPORTANT: Please consult with the regulating council for
local design requirements prior to the design and construction of a
retaining wall. Councils in general require that retaining walls be
designed and certified by a suitably qualified engineer where the
wall is over 0.5m in height and/or where there is surcharge loading
such as a roadway, house, or other structure near the wall.
Refer to Keystone and Pyrmont ‘No-Fines Concrete’ Guidelines
for engineered retaining walls to AS4678.
• Two sets of pin holes are provided in Keystone units.
• For near vertical construction, install pins in the front
holes.
• For 1 in 8 setback construction, install pins in the back
holes.
Fig E1 — Installation of Pins
Surcharge Loading
Wall Height (mm)
Backfill
Near 1 in 8
Type
Vertical Setback
SETBACK Poor 800 900
Average 900 1000
Good 1000 1200
Poor 600 900
Average 700 900
Good 800 1100
Poor 400 500
Average 500 600
Good 600 800
• Near vertical installation must be used when designing
walls with curves or corners.
E6 July 2008 | BORAL MASONRY DESIGN GUIDE
No Surcharge Loading
15° Sloped Backfill
Driveway/Carpark Loading (5kPa)
Table E1 — Maximum Wall Height for Gravel-Fill Walls

• For curved installations, leave a small gap between units
for convex curves. Concave curves will require a small
overlap of adjacent units. Refer to curve installation
details on Page E9 of this guide.
• If backfill is required behind the drainage zone, place
and compact existing site soils in 200mm maximum lifts.
Heavy clays and organic soils are not recommended due
to water holding problems.
Compacted backfill
soil (if required)
Drainage pipe
Free draining
granular material
Compacted footing
Backfill
BORAL MASONRY DESIGN GUIDE | July 2008
Native soil
Fig E2 — Typical Installation Detail — Keystone Gravity Wall
Granular material
for drainage
300mm
600mm min.
Queensland Book 4 E
• Provide a filter fabric between the drainage layer and the
backfill if the type of backfill is likely to wash into the
drainage layer and clog it.
• Use only walk-behind compaction equipment within
1000mm of the wall face to prevent movement of the
Keystone units.
• In areas of possible vandalism, it is recommended that
capping units be secured using a masonry adhesive.
Cap Unit
150mm min
Keystone or Pyrmont
units
Optional 1:8 wall setback
with Keystone units
12-20mm free draining
granular material, fill all
voids in and around units
Drainage pipe (if required)
First course to be buried below
final ground level (to engineer's
specification - 100mm min.)
Compacted roadbase,
crushed stone or gravel
levelling pad
Fig E3 — Typical Construction Detail — Keystone Gravity Wall
H
E7

Queensland Book 4 E
Typical Installation Details
Omit one
pin only
FIRST COURSE SECOND COURSE
Align centre of unit
with face of
adjoining wall
No pin in
overlapping
unit
Align face of unit with the
centre line of adjacent unit
No pin in
overlapping
unit
Fig E4 — 90° Internal Corner — Standard Keystone Units
FIRST COURSE SECOND COURSE
Cut to suit on site
Omit one
pin only
Cut to suit on site
Fig E5 — 90° Internal Corner — Flushface Keystone/Pyrmont Units
Align face of unit with the
centre line of adjacent unit
E8 July 2008 | BORAL MASONRY DESIGN GUIDE

222mm
455mm
455mm
450mm
3 unit 90 corner : r = 900mm
4 unit 90 corner : r = 1250mm
5 unit 90 corner : r = 1540mm
6 unit 90 corner : r = 1830mm
7 unit 90 corner : r = 2120mm
455mm
BORAL MASONRY DESIGN GUIDE | July 2008
Pyrmont
corner unit
455mm
Use front pin holes for curves.
Maintain a small overlap
between units.
Fig E7 — Concave Curve
Queensland Book 4 E
Pyrmont
corner unit
FIRST COURSE SECOND COURSE
Bolster
backs as
required
Fig E6 — 90° External Corner
Pyrmont Units Only
Radius ‘r’
Fig E8 — Convex Curve
Use front pin holes for curves. Maintain a
small gap between units.
E9

Queensland Book 4 E
Drill and
install fixing
pin
Bolster backs as
required
225˚ corner unit – to be cut
and bolstered from
Keystone/Pyrmont Unit
Next course is a mirror image.
Fig E9 — 225° External Corner
Flushface Keystone/Pyrmont Units
160mm riser
40mm
10mm
100mm
10mm
Tread approx. 290mm
for 40mm pavers (30˚)
290mm Treads
Fig E10(b) — Plan view of step through Keystone
Fig E11 — Keystone section through steps
Keystone unit
Keystone cap unit
Fig E10(a) — Stepped Capping Units
Compacted bedding sand
40mm Boral Pavers
10mm mortar joint
Keystone Flushface Caps
Sand : cement = 6 : 1
Bedding sand –
compact before laying treads
E10 July 2008 | BORAL MASONRY DESIGN GUIDE

‘No-Fines Concrete’ Wall Construction Guidelines
The ‘No-Fines Concrete’ backfill system increases the mass of
Keystone/Pyrmont allowing the maximum heights in Table E1
to be exceeded without using geogrids.
This is ideal for boundary walls where the geogrids would
otherwise cross the boundary line.
No-Fines Concrete shall consist of cement, water and coarse
aggregate. Cement will comply with the definitions for cement per
AS3972 : 1991 — ‘Portland and Blended Cements’. The quantity
of cement is specified as 210kg/m3 with a total water/cement
ratio of between 0.45 and 0.55.
Retained soil
25MPa concrete
footing on 150kPa
allowable bearing
capacity material
(see note below
Table E2)
BORAL MASONRY DESIGN GUIDE | July 2008
T
600mm min.
Cap unit
Filter Fabric
15MPa ‘No-Fines’ concrete.
All voids within and around
units to be completely filled.
Keystone or Pyrmont unit
Sub-soil drain
connected to
stormwater system
or flood pit
Pour no-fines concrete
directly onto prepared
foundation material
150mm min
Blocks embedded to
engineer's detail
(100mm min)
Fig E12 — Typical Construction Detail — Keystone No-Fines Concrete Mass Gravity Wall
Queensland Book 4 E
The particle size distribution of the aggregate shall comply with
the limitations for the nominal single sized 20mm aggregate
specified in AS2758.1.
NOTES:
• 15MPa No-Fines concrete with a 6:1 ratio (Gravel: Cement).
• The density of this product will vary with the density of
the aggregate used. The density range may be from
1650kg/m3 to 2100kg/m3. Table based on density of
2100 Kg/m3.
• The void ratio of the mix is expected to be between 20%
and 30% and should be free draining.
Table E2 — Maximum Wall Heights for No-Fines Concrete Wall Construction
Wall Height Retained Soil Retained Soil Retained Soil
CLAY f = 26° (POOR) SAND f = 30° (AVERAGE) GRAVEL f = 34° (GOOD)
‘H’ (mm) ‘T’ (mm) ‘T’ (mm) ‘T’ (mm)
1000 550 500 450
1400 750 700 650
1800 NA 1000 850
2200 NA 1250 1000
2600 NA 1350 1200
f Denotes the internal angle of friction of the retained material
Non-shaded Area = Compacted Roadbase Footing Shaded Area = Concrete Footing as per Fig E12
If material below no fines concrete is of poor quality, then the material must be replaced with a 150mm thick layer of crushed sandstone.
H
E11

Queensland Book 4 E
• The compressive strength should generally exceed
15MPa for design purposes.
• This product has no slump and exerts similar pressures
on the soil and formwork, as does loosely poured
aggregate.
Table E2 is prepared as per AS4678 : 2002, and is based
on a 5kPa surcharge loading at the top of the wall. This
table is supplied as a guide, and does not form any part
of any contract with the user.
• The maximum slope of the backfill behind the wall is to
be 5% (1 vertical to 20 horizontal).
• The vertical height of any pour of ‘No Fines’ concrete is
limited to 600mm. Each pour must be allowed to harden
prior to pouring the next lift. Alternatively the wall may
be propped to support the lateral load from the wet
concrete.
• For higher walls or walls with a greater surcharge loading,
Geogrid soil reinforced construction is required.
• For walls founded on clay with a height greater than 2.0m,
Geogrid reinforcement is required.
• Global stability considerations should be checked by an
engineer in poor clay conditions.
• Design assumes a dry excavation (i.e. water table is below
bottom of footing level). If ground water appears in the
excavation, the wall is to be re-designed by a suitably
qualified engineer.
Construction Steps
Special purpose construction such as waterside walls, post
fixing, earthquake zones, and terraces will require additional
engineer’s design.
STEP 1:
Excavation/Preparation of Levelling Pad
For walls less than 900mm high, excavate a trench 600mm
wide and sufficiently deep to allow a levelling base of 150mm
+25mm height for each course. Spread coarse sand or
12-20mm gravel for the levelling base and compact.
For higher walls or in poor foundation material, a footing as
shown in Fig E12 may be necessary. Refer to Table E2.
STEP 2:
Installing the First Course
Lay the first course of units side to side over the prepared
base, with the 12mm pinholes on top and kidney holes on
the underside. Maintain the required distance between pinhole
centres of adjacent units. In straight walls, units will touch.
In concave or convex curves, the units will overlap or require
spacing respectively. Refer to Figs E7 and E8 for curve installation
details.
STEP 3:
Installing the Pins
Place the high strength fibreglass connecting pins into each
unit. Use the front holes for a near vertical setback (corners
and curved walls). Use the rear holes for a 1 in 8 setback
(i.e. for every course the wall will set back 25mm for straight
walls only).
STEP 4:
Additional Courses
Sweep the top of the previous course of units clean of any loose
gravel. Place the next course of units so that the kidney holes
fit over the pins of the two units below. Pull the unit towards
the face of the wall until it locks with the pins on both sides.
Repeat steps 3 and 4.
STEP 5:
No-Fines Concrete Backfill
Backfill the wall with ‘No Fines’ concrete. All voids inside and
between the units must also be filled. The vertical height of any
pour of ‘No Fines’ concrete is limited to 600mm. Each pour must
be allowed to harden prior to pouring the next lift. Alternatively
the wall may be propped.
STEP 6:
Installing Capping Units
Lay capping units, backfill and compact to required grade. In
areas accessible to public vandalism, it is recommended that
the capping units be secured using masonry construction
adhesive or epoxy cement.
E12 July 2008 | BORAL MASONRY DESIGN GUIDE

Geogrid Soil-Reinforced Wall Construction Guidelines
For taller, more critical walls, the combination of Keystone
units with geogrid soil reinforcement allows walls to be built to
heights of 12m and greater, without costly structural footings.
When placed between layers of compacted soil, geogrids create
a reinforced soil mass, which essentially acts as a larger gravity
wall structure.
Geogrids can be used with most existing site-soils and are not
affected by water, micro organisms, alkali or acidic soils. Consult
your engineer for design requirements of Keystone walls using
geogrid soil reinforcement.
NOTES:
• Table E3 is prepared as per AS4678 : 2002. Suitability of
BORAL MASONRY DESIGN GUIDE | July 2008
Queensland Book 4 E
the information contained in the table must be referred to a
qualified professional engineer. These tables are supplied as a
guide, and do not form any part of any contract with the user.
• Table E3 is based on foundation material with minimum
200kPa bearing capacity.
• Where site conditions and loadings vary from those in the
table, professional engineering advice should be obtained.
• The minimum embedment of wall below ground level is
assumed to be H/20, or 100mm, whichever is greater.
• The length of the 15° backfill slope is assumed to be equal
to the height of wall, H.
Table E3 — Maximum Wall Heights for Geogrid Soil-Reinforced Walls
Surcharge Wall Geogrid Geogrid Height Above Geogrid Length
Height Layers Levelling Pad L (m)
H (m) Layers Soil Type (phi)
1 2 3 4 5 6 7 25 30 35
10 Degree 1.1 2 0.2 0.8 — — — — — 1.5 1.5 1.5
3xT 1.5 3 0.2 0.8 1.2 — — — — 1.9 1.5 1.5
1.9 3 0.4 1.0 1.6 - — — — 2.1 1.8 1.6
2.3 4 0.2 0.8 1.4 2.0 - — — 3.4 2.1 1.8
2.7 5 0.4 0.8 1.2 1.8 2.4 - — 3.9 2.4 2.1
3.1 6 0.2 0.6 1.0 1.6 2.2 2.8 - 4.8 2.8 2.4
5kPa 1.1 2 0.2 0.8 — — — — — 1.5 1.5 1.5
Driveway 1.5 3 0.2 0.6 1.2 — — — — 1.9 1.5 1.5
3xT 1.9 3 0.4 1.0 1.6 — — — — 2.2 1.8 1.6
2.3 4 0.2 0.8 1.4 2.0 — — — 2.5 2.0 1.8
2.7 5 0.2 0.4 1.2 1.8 2.4 — — 2.8 2.3 2.1
3.1 6 0.2 0.6 1.0 1.6 2.2 2.8 — 3.2 2.6 2.4
*Geogrid with Tul=55kN/m *Geogrid lengths for 5kPa driveway are based on the load being applied a minimum of 800mm from the face of the retaining wall.
E13

Queensland Book 4 E
Geogrid sections are
located over pins at the
front, pulled taught and
staked at the back
Compacted
backfill soil
Drainage pipe
Free draining
granular material
Compacted
roadbase footing
Reinforced Soil Zone
Native soil
L
Native soil
Fig E13 — Typical Installation Detail — Keystone/Pyrmont Geogrid Reinforced-Soil Wall
Granular
material
300mm
600mm min.
Cap Unit
150mm min.
Keystone or Pyrmont unit
12-20mm free draining
granular material, fill all
Compacted backfill material
Geogrid soil reinforcement
to engineer's specification
Drainage pipe (as required)
First course to be embedded
below final ground level to
engineer's detail (100mm min.)
Compacted roadbase or
concrete footing
Fig E14 — Typical Construction Detail — Keystone/Pyrmont Geogrid Reinforced-Soil Wall
E14 July 2008 | BORAL MASONRY DESIGN GUIDE
H

Typical Specification for
Keystone or Pyrmont
Retaining Walls
1. Scope of Work
1.1 Extent
This specification covers the works for construction of segmental,
reinforced-soil retaining structures. The works include footing
excavation, foundation preparation, drainage, backfill and
compaction and related items necessary to complete the work
indicated on drawings and as further specified.
All retaining wall construction is to be carried out in accordance
with the levels, distances and details as shown on the drawings
and in accordance with this specification.
The Keystone reinforced retaining wall system shall also
be constructed in accordance with the manufacturers
installation guidelines by a suitably qualified and experienced
contractor.
1.2 Responsibilities
The Contractor shall be responsible for carrying out the
installation of all retaining walls in accordance with this
specification and the associated contract documents.
2. Standard Specification
Wherever reference is made to Standards Association
of Australia (SAA) the requirements of the editions and
amendments, shall apply to the relevant materials or operations
and be deemed to be incorporated in this specification.
In the case of a conflict between the referenced standard
specification and code and this specification, the more stringent
provisions shall apply.
The following is a summary of standard specifications applicable
to this subsection of the work:
AS1012 Methods of Testing Concrete
AS4456 Concrete Masonry Units
AS3600 Concrete Structures
AS4456.4 Masonry Units — Compressive Strength
AS4678 Earth Retaining Structures
AS1289 Methods of Testing Soils
Materials or operations not covered by the above standard
codes shall conform to the appropriate Australian Standard.
BORAL MASONRY DESIGN GUIDE | July 2008
3. General Requirements
Queensland Book 4 E
3.1 General
Terms used in this specification shall have the meanings
assigned to them as follows:
‘Approved’ shall mean approved in writing by the Engineer.
‘Or equal approved’ shall mean equivalent in performance,
quality and price to that specified and approved by the
Engineer.
Where limits to the properties of soils are defined elsewhere
herein these properties shall be determined by the methods
laid down in AS1289.
The term ‘construction area’ in this Part shall be defined as an
area to be excavated or an area to be cleared and filled.
3.2 Regulations
The Contractor shall comply with all relevant Acts, Regulations
and By-Laws in respect of all work specified herein, including
temporary timbering, strutting, guard rails and all safety
measures to be adopted.
3.3 Certification
The Contractor’s Geotechnical Engineer shall certify that the
bearing capacity of the foundation is as per the foundation
requirements specified on the drawings. The Geotechnical
Engineer shall also inspect and certify that the Reinforced
Soil Block material is as specified on drawings with regard
to friction angle, and bulk density.
4. Materials
4.1 Masonry Units
The retaining wall units shall be manufactured in accordance
with AS4456 Concrete Masonry Units. Block types and sizes
for Keystone retaining walls shall be as shown on the drawings
or specified herein.
4.1.1 Tolerance
Permissible tolerance in the manufacture of retaining wall units
shall comply with AS4456.3 - 1997. In the case of Keystone units,
the tolerance of ± 2mm shall not apply to profiled or textured
faces. Non conforming concave distortions shall be rejected.
E15

Queensland Book 4 E
4.1.2 Strength
Retaining wall units shall be manufactured with a minimum
compressive strength of 10MPa. A minimum of ten (10) samples
must be tested to obtain a mean compressive strength, tested
to failure as per AS4456.4 — 1997 under normal compressive
and laboratory conditions.
4.1.3 Colour
The colour and texture of masonry units shall be as specified
and shall remain consistent with the ‘sample range’ approved
by the project Superintendent.
4.1.4 Handling/Storage/Delivery
Keystone units shall be delivered on pallets to minimise
damage during transportation. The Contractor shall store
and handle units so as to prevent units from damage, which
may affect the aesthetic quality or structural integrity of the
finished wall.
4.2 Connecting Pins
High strength pultruded fibreglass pins shall be used to
interlock and align all Keystone units in a running bond pattern.
Pins shall also provide an integral connection between the
Keystone units and the geogrid.
4.3 Geogrids
The reinforcing elements for the reinforced soil structure shall
be as shown on the drawings.
If required, each consignment of geogrids delivered to site shall
be accompanied by a Quality Control Tensile Test Certificate
from the manufacturer.
4.4 Approved Reinforced Soil Block Backfill
Material for backfilling between geogrids for the Keystone
retaining wall shall be ‘Approved Backfill’ defined as sand,
crushed sandstone or broken rock obtained from excavations
or approved borrow areas. Such material shall be
• Free of rock fragments greater than 75mm in size.
• Free of clay lumps retained on a 75mm sieve.
• Free of organic matter.
• Within the following grading requirements;
Sieve Size % Passing by Weight
75mm 100
26.5mm 50 - 100
4.75mm 25 - 75
0.425mm 10 - 50
0.075mm 0 - 20
• Non-plastic in that the fraction passing 0.425mm has a
Plasticity Index of not greater than 15.
• Capable of being brought to a moisture content suitable
for compaction as specified elsewhere herein, under the
weather conditions prevailing on site.
The ‘Approved Backfill’ shall be stockpiled on site, and
inspected and approved by the Geotechnical Engineer that the
material satisfies the specification above the design friction
angle and dry density values as specified on drawings. Testing
for dry density and friction angle shall be in accordance with
section 6 herein.
4.5 Drainage
All retaining walls are to contain drainage systems that
prevent the build up of hydrostatic pressure behind walls. This
is to include a 12-20mm free draining clean hard aggregate,
used to fill all voids within the retaining wall units and to extend
300mm behind the units.
Drainage is to be installed as per the drawings and as per the
manufacturers recommendations.
4.6 Concrete Works
All concrete for use in footings for retaining walls shall have a
compressive strength after 28 days of 25MPa unless specified
otherwise.
The supply, placement, finishing and curing of reinforcement
and insitu concrete shall comply in every respect with
AS3600.
4.7 Hold and Witness Points
The following shall be deemed a Hold Point:
• Submission of test results and samples of all retaining
wall components.
The following shall be deemed a Witness Point:
• On-site slump and strength testing of concrete.
E16 July 2008 | BORAL MASONRY DESIGN GUIDE

5. Construction of Keystone/Pyrmont
Retaining Walls
5.1 Foundations
Excavation is to be to the lines and grades shown on the
drawings. The reinforced soil block foundation size shall be
constructed as per drawings unless alterations are made by
the Geotechnical Engineer, who may require tests on the
sub-grade material, to be carried out by a registered N.A.T.A.
Testing Laboratory.
The reinforced soil block foundation subgrade shall be proof
rolled with a heavy steel drum roller (minimum applied
intensity of 4t/m width of drum with at least 8 passes)
without vibration. Any material which is soft, visibly deformed,
unstable or deemed unsuitable by the Contractor’s geotechnical
consultant shall be excavated and replaced with approved
fill and compacted to achieve dry densities of between 98%
and 103% of Standard Maximum Dry Density at moisture
content of ±2% of Standard Optimum Moisture Content.
The foundation shall be inspected and approved by the
Geotechnical Engineer, who shall verify that the foundation
bearing capacity exceeds the required bearing capacity as
specified on drawings. The approval of the reinforced soil block
foundation shall be deemed a HOLD POINT.
Detailed excavation for the mass concrete footing shall proceed
following acceptance of the foundation. The footing subgrade
shall be inspected by the Contractor’s Geotechnical Engineer
and any areas deemed soft, unstable or unsuitable by the
Geotechnical Engineer shall be excavated and replaced as
described above.
The footing shall be constructed as shown on the drawings.
It could be shown as compacted roadbase or concrete. For
concrete, the footing shall be poured to the correct level
using formwork edge boards, or other methods which ensure
the correct level of the footing. The concrete footing shall
be screeded flat. The level of the footing or first course of
blocks shall be verified by survey methods, and approved by
the Contractors QA representative. This shall be deemed a
WITNESS POINT.
5.2 Unit Installation
Foundations and all courses are laid level. Batters are achieved
by inserting the fibreglass connecting pins into the appropriate
holes. The Keystone retaining walls shall be constructed with
batters as shown on the drawings.
First course of units shall be placed side by side on the base
levelling pad. Units shall be levelled side to side and front
to back and checked for alignment. The accurate placement
BORAL MASONRY DESIGN GUIDE | July 2008
Queensland Book 4 E
of the first course is most important, to ensure acceptable
horizontal and vertical tolerances. Two fibreglass connecting
pins shall be inserted into the appropriate holes to interlock
and align units.
The front set of pin holes shall be used for near vertical
setback.
The rear pair of holes shall be used for 25mm (1:8) setback.
All voids in units and between units shall be filled with
drainage fill as specified in section 4.5. Drainage fill shall
extend to 300mm behind units.
Units shall be placed in a running bond pattern. Top of units
shall be swept clean of excess material. Kidney holes of units
above shall be positioned over pins in units below. Units shall
be pulled toward the face of the wall to interlock the pins
with units on either side. Levels and alignment of each course
shall be checked. Each course shall be filled, backfilled and
compacted prior to placement of the next course. The Keystone
wall shall be surveyed for vertical level tolerance every 3
courses. This shall be deemed a HOLD POINT.
5.3 Drainage Installation
The drainage measures shall be installed as shown on drawings.
100mm diameter agricultural pipe shall be used for subsoil
drainage behind the first course of Keystone units. The subsoil
drain shall be placed with a minimum 1% fall as shown on
drawings.
‘T’ piece connection fittings shall be used at all outflow points
to connect the subsoil drainage to a 100mm diameter pipe
stub which extends 300mm past the face of the Keystone wall.
The pipe stub material shall be UPVC or HDPE and shall be
approved by the project Superintendent.
The outflow points shall be at a maximum of 60m centres.
The locations of the outflow points shall be determined by the
Superintendent. The outflow pipe stub shall be supported on
the concrete footing, and shall pass between two Keystone
units with 60mm of the facing removed by sawcutting. The
gap above the pipe in the first course shall be neatly patched
with cement mortar.
The drainage measures shall be inspected by the QA
representative after the installation of the first and second
course is complete. Inspection and approval of the drainage
installation shall be deemed a HOLD POINT.
E17

Queensland Book 4 E
5.4 Placement of Geogrid
The Geogrid shall be placed between Keystone units as
specified on the drawings. Geogrids shall be cut to the required
length. Geogrids may be longer than required, but shall not be
shorter than the specified length shown on the drawings.
The Geogrids shall be placed with the roll direction perpendicular
to the face of the Keystone wall. Correct orientation of the
geogrids shall be verified by the Contractor.
After compaction, the layer of select backfill below each geogrid,
shall be raked to a depth of 25mm to ensure good interlock
between the geogrid and the select backfill. The Geogrid shall
be laid horizontally on compacted backfill and connected to the
Keystone units by hooking geogrid over the fibreglass pins. The
geogrid shall be pulled taut against pins to eliminate slack from
connections and loose folds. The back edge shall be staked or
secured prior to backfilling to maintain tension in the geogrid.
Each block shall be checked for level accuracy, as out of position
transverse bars will lead to sloping blocks. If the course above a
layer of geogrid is found to be not level, then the blocks shall be
removed, and the geogrid repositioned to ensure levelness.
For a straight length of wall, the geogrids shall be laid side
by side without joints or overlaps. Where the wall is convex,
the geogrids shall not be cut, but shall be overlapped with
a minimum of 75mm of compacted fill between them. For a
concave wall the position of the layers of grid shall be alternated
between consecutive geogrid layers to cover the triangular gaps
between strips of geogrid. Refer to Fig 5.4.
Geogrid
Wall Face
Fig 5.4 — Typical Geogrid Layout
The QA Representative shall inspect and keep records of the
position of grid and the type of grid placed for each layer of
geogrid. The number of courses between each successive layer
of geogrid shall be noted. The QA Representative shall also
check this. This shall be deemed a WITNESS POINT.
5.5 Placement of Reinforced Soil Backfill
Prior to placement of ‘Approved Backfill’ in the reinforced soil
block, the Geotechnical Engineer shall approve the material and
confirm that the friction angle and dry density of the material
is in accordance with the drawings for that particular section
of the project. This shall be deemed a HOLD POINT.
All backfill imported or otherwise shall be as specified on the
drawings. Backfill shall be spread in a maximum of 200mm
layers, in such a manner that minimises the voids directly
underneath the geogrid. Fill should be deposited using suitable
plant which causes fill to cascade onto geogrids. Placement of
fill on top of the geogrids shall start from the wall face and
work back from the wall face in order to minimise slack or loss
of pretension from the grid. Care should be taken to not mix
the reinforced soil block backfill material with the drainage
material. If backfill material mixes with the drainage material,
then the drainage material is to be removed and replaced with
clean material.
Compaction shall be to 98% of Standard Maximum Dry
Density. Compaction shall start at the wall face and work
back from the wall face. Compaction testing shall be in
accordance with section 6 specified herein. Compaction testing
shall be deemed a WITNESS POINT.
Tracked construction equipment shall not be operated directly
on the geogrid. A minimum thickness of 150mm of backfill
material shall be placed prior to the operation of tracked
construction equipment. Rubber tyred equipment may pass
over the geogrids at very slow speeds. Sudden braking or
sharp turning shall be avoided to prevent displacement of
geogrids.
Construction plant and all other vehicles having a mass
exceeding 1000kg shall be kept at least 1m from the back of
the Keystone units. Compaction of the 1m zone behind the
Keystone units shall be restricted to:
• Vibrating rollers with a mass < 1000kg
• Vibrating plate compacters with a mass < 1000kg
• Vibro tampers having a mass < 75kg
E18 July 2008 | BORAL MASONRY DESIGN GUIDE

Surface drainage during and after construction of the wall shall
be provided to minimise water infiltration in the reinforced
soil zone.
5.6 Hold and Witness Points
The following shall be deemed a HOLD POINT:
• Approval of foundation material by the Geotechnical
Engineer.
• Inspection and approval of ‘Approved Backfill’ for use in
reinforced soil block by the Geotechnical Engineer.
• Survey of the Keystone Wall every 3 courses.
• Inspection and approval of the drainage installation by
the QA Representative.
The following shall be deemed a WITNESS POINT:
• Survey verification that the first course is installed at the
correct level, and inspection and approval of footing by
the QA Representative.
• Inspection of level and type of geogrid at each layer by the
QA Representative.
• Compaction Testing by the Geotechnical Engineer.
6. Material Testing
6.1 Testing of ‘Approved Backfill’
Each source of ‘Approved Backfill’ shall be pretreated by 5
cycles of repeated compaction, and then tested for dry density
and friction angle. Material for use as ‘approved backfill’
shall be inspected and approved for use by the Geotechnical
Engineer. A stockpile at least equivalent to 5 days reinforced
soil wall construction shall be maintained on site at all times.
This will allow time for friction angle testing of the approved
backfill should visual inspection of the material when it is
received on site indicate that testing is required.
Not withstanding the above the following minimum testing
shall be carried out:
• Dry Density shall be tested at a frequency of 1 test per
400m 3 of approved backfill.
• Friction angle shall be tested at a frequency of 1 test per
2000m 3 of approved backfill.
If the dry density results are not within ±5% of the specified
design value, then the Engineer shall be notified, and the
material not approved for use until the design has been
verified.
BORAL MASONRY DESIGN GUIDE | July 2008
Queensland Book 4 E
6.2 Testing for Compaction
Compaction will be checked by standard maximum dry density
test and field density test for materials other than sand or by
the density index and field density tests for sands as specified
on drawings and herein.
Tests will be carried out in groups of at least three, and
compaction of the layer concerned will be considered to be
satisfactory if no single result falls outside the specified
density range. Should the results not reach this standard the
Sub-Contractor shall again roll the area, if necessary after
scarifying, adding water, blading to reduce the moisture content
and/or removing and replacing excessively moist fill as may
be required.
Should the Geotechnical Engineer consider that the depth
of insufficiently compacted material is greater than can be
effectively compacted from the surface, material shall be
removed to a depth at which compaction is satisfactory and
replaced and compacted in 200mm maximum layers.
The standard maximum dry density referred to herein for
materials other than sand shall be maximum standard dry
density as determined in accordance with AS1289 - Test
numbers 5.1.1.
The modified maximum dry density referred to herein for
materials other than sand shall be the maximum modified dry
density as determined in accordance with AS1289 - Test 5.2.1.
The field density referred to herein for all materials shall be the
dry density of the material in place as determined in accordance
with AS1289 - Test 5.3.1.
The percentage of the standard maximum dry density (Dry
Density Ratio) elsewhere herein for materials other than sand
shall be calculated from the formula given in AS1289.5.4.1.
The maximum and minimum densities of cohesionless materials
shall be determined in accordance with AS1289 - Test E5.1.
The Density Index specified elsewhere herein for sands shall
be calculated from the formula given in AS1289.E6.1.
6.3 Frequency of Testing
The following testing frequencies relate to acceptance on a
‘not-one-to-fail’ basis. The testing should be carried out in
essentially randomly chosen locations and at the frequencies
as given below. However, it may be appropriate to undertake
testing in specific locations, based on visual appearance or
past experience.
Where a test or group of tests is carried out on an area which
has been subjected to essentially the same preparation and
compaction procedures, the whole of this area is considered
E19

Queensland Book 4 E
to be represented by this test or group of tests. The uniform
area is generally known as a work lot. On this basis, if one
or more tests indicate compliance with the specification has
not been achieved, the whole of the area which has been
submitted for testing is deemed not to comply, unless it can
be demonstrated that the area in which the non-complying
test result(s) can reasonably be separated from the whole. It
should not be assumed a test result applies only to the area
immediately surrounding it.
Required frequency of testing, is not less than 1 test per layer of
200 mm thickness per material type per 400m3 which is 1 test
per layer per 100 linear metres of wall construction. If different
sources of ‘approved backfill’ are used within the 100 linear
metre work lot, then 1 test per type of material is required. If
the work is staged in sections of less than 100 linear metres,
then 1 test per section is required.
The testing frequency may be re-assessed to the approval of
the Engineer, if a high degree of uniformity becomes evident
during construction.
E20 July 2008 | BORAL MASONRY DESIGN GUIDE

BORAL MASONRY
Build something great
Masonry Design Guide
SEGMENTAL BLOCK RETAINING WALLS QUEENSLAND BOOK 4
F CUSTOM ENGINEERED WALLS
44F

Queensland Book 4 F
Engineered
Retaining Wall Systems
for domestic and commercial landscaping, roadside
and custom engineered retaining wall applications
Boral Keystone, Pyrmont and Keysteel Retaining Wall
Systems provide a proven and versatile platform for the
development of custom engineered high performance
retained earth structures.
Boral has developed alliances with a number of suitably
experienced engineering companies that can provide
professional assistance with the custom design and
installation of Keystone, Pyrmont and Keysteel retaining
structures.
Please contact Boral Masonry in your region for assistance
with your high performance, engineered retaining wall
projects.
F2 July 2008 | BORAL MASONRY DESIGN GUIDE

Keysteel Custom Engineered
Retaining Wall Systems
Gravity Retaining Walls
Mass Gravity Retaining Walls
Geogrid Reinforced-Soil Retaining Walls
Steel-Ladder Reinforced-Soil Retaining Structures
Bridge Abutments
Stream or Drainage Channels
Erosion Prevention
Tunnel Access Walls
Wing Walls
Embankment Stabilisation
Terraced Walls
Seawall Applications
Soil-Anchor and Rock-Anchor Walls
Fencing, Railings and Barriers
BORAL MASONRY DESIGN GUIDE | July 2008
Queensland Book 4 F
Keysteel Custom Engineered Retaining
Wall Systems
Boral Keysteel is a high performance engineered
retaining wall system for applications requiring wall
heights in excess of 6m and/or where critical surcharge
loadings are present. Boral Keysteel is an internationally
proven system that integrates the superior strength
and durability of Keysteel blocks with steel-ladder soilreinforcement
to provide engineered solutions for the
most demanding retaining structures.
F3

Queensland Book 4 F
455
Standard Unit
455
Standard Cap
315
275
200
100
Steel Pins
(hot-dip galvanised)
484
Flushface Cap
Lifting Bars
484
Flushface Unit
Keygrid Geogrid Soil Reinforcement
315
275
100
Availability and Colours
• All Keysteel products are made-to-order.
• Lead times apply Please consult with the Boral Masonry
sales office in your region.
Natural
Charcoal
Parchment
Terracotta
200
Keysteel ®
High Performance Engineered
Retaining Wall Systems
INTRODUCTION
Boral Keysteel is an internationally
proven, high performance retaining
wall system that integrates the
superior strength of Keysteel blocks
with steel-ladder soil-reinforcement,
and is ideally suited to retaining
structures in excess of 6m high and
for critical surcharge loadings.
DESIGN CONSIDERATIONS
Boral Keysteel installations are
individually engineered to match
the application criteria.
Boral has developed alliances with
a number of suitably experienced
engineering companies which can
provide professional assistance
with the design and installation of
Keysteel retaining structures.
Specifications
Please contact Boral Masonry
Technical Services in your region for
assistance with Keysteel projects.
COLOURS
Boral Keysteel is made-to-order in the
same range of colours as Keystone,
allowing integration of the two
products within the one project. Please
refer to colour swatch information for
an indication of current colours.
Description HxLxDmm Wt kg N°/m2
Standard Unit 200x455x315 36 11
Standard Cap 100x455x275 20 2.2/lin mtr
Flushface Unit 200x484x315 39 11
Flushface Cap 100x484x275 21 2.2/lin mtr
Pins (steel) 2 pins per full unit
hot-dip galvanised steel
Lifting Bars (Keysteel units should be lifted by
two people using the Keysteel lifting bars)
F4 July 2008 | BORAL MASONRY DESIGN GUIDE

Typical Keysteel ® Application Layout
Wall face
Keystone unit
Fig F1 — Typical Construction Detail — Keysteel wall
Soil
reinforcement
ladder
Keysteel unit
Keysteel unit
Fig F2 — Typical Curved Wall Detail — Keysteel
BORAL MASONRY DESIGN GUIDE | July 2008
Pylon
Queensland Book 4 F
Cut ladder around pylon Where piles prevent installation of
ladders refer to engineers detail.
Keysteel unit Soil reinforcing
ladder
Fig F3 — Typical Straight Wall Detail — Keysteel
F5

Queensland Book 4 F
Typical Soil-Anchor Application
Granular backfill
Stiff firm soil
5˚
Soil failure plane
Soil anchors to site
specific design
Geogrid (if
required)
Stiff firm soil
TYPICAL PLAN VIEW
Galvanised
steel pipe
Galvanised pipe
Soil anchors
1200mm cts nominal
Keystone unit
Top of wall stepped (optional)
Galvanised pipe,
loop connector and
soil anchors
(staggered installation)
Footing step
Finished grade
TYPICAL WALL ELEVATION
(optional) Threaded pipe
coupling
300mm
nominal
TYPICAL SIDE ELEVATION
1
8
Cap unit
See connection detail
Keystone units
Drainage pipe
Leveling pad to
engineer's detail
Finished grade
Fig F4 — Typical Soil-Anchor Detail
Soil anchor to
design details
TYPICAL CONNECTION DETAIL
Galvanised pipe
loop connector
Keystone unit
Geogrid
Galvanised steel pipe
Loop connector
Granular fill
F6 July 2008 | BORAL MASONRY DESIGN GUIDE

Typical Rock-Anchor Application Layout
Reinforcing bar to
project specifications
Drainage net
to design details
Temporary concrete and
mesh facing support
system with drainage to
design details
Rock anchor
system
to design
details
Geogrid to project
specifications
Expansion joint material
to design details
Finished grade
300mm
nominal
TYPICAL WALL ELEVATION Footing step
1500mm
typical
Granular material
wrapped in geotextile
BORAL MASONRY DESIGN GUIDE | July 2008
1
8
TYPICAL SIDE ELEVATION
Drainage net
TYPICAL PLAN VIEW
Reinforcing bar
to design details
Rock anchors
Concrete backfill
Queensland Book 4 F
Temporary face
support and drainage
system
Keystone unit
Top of wall stepped (optional)
Geogrid Soil Anchor to
design details
Keystone cap
See anchorage detail
Keystone unit
Horizontal reinforcing
bar to design details
Vertical reinforcing bar
to design details
Concrete backfill to
design detail
Geogrid at 600mm
vertical centres extended
to wall face between
reinforcing bar
Drainage pipe
Levelling pad
Finished grade
Fig F5 — Typical Rock-Anchor Detail
Rock anchor
to design detail
Steel plate and securing
nuts to design detail
TYPICAL ANCHORAGE DETAIL
Keystone unit
Geogrid
Reinforcing bar
to design detail
Thread bar to
design details
Concrete
backfill
F7

Queensland Book 4 F
Typical Seawall Application Layout
Engineering
All water application projects should be designed by a suitably
qualified engineer. The Keystone Retaining Wall System has
been used in numerous international projects where the
blocks are subjected to high velocity flood water, wave action
and tidal action.
Spacing of Geogrid
As with all geogrid soil reinforced Keystone walls, the spacing
of the geogrid should not exceed 600mm, to prevent bulging
between the grid layers.
Suitability of Keystone Blocks in a Seawall
Application
It is recommended that if the Keystone units are submerged
in salt water, then marine grade Keystone units should be
used. Minimum order quantities apply to these units.
NOTE: Product colours will be different due to the use of
marine grade cement.
Impermeable soil layer
Native soil
Free draining granular
material (less than 10%
passing the #200 sieve,
no organic material)
Geogrid as per
design
Compacted
aggregate or
crushed rock
300mm
Undermining of Foundation Wall
Greater embedment of units, concrete footings (piered or
otherwise), Keystone units keyed to a concrete foundation are
all means of preventing undermining of the wall foundation.
Rip-Rap in front of the wall will also help to prevent erosion.
Loss of Material through Wall Face
Filter fabric used behind the 300mm drainage layer will prevent
loss of retained soils during fluctuation in water level.
Differential Water Pressures
Fluctuations in water levels and rapid draw down may induce
differential water pressures across the face of the wall and need
to be addressed.
Test Reports
Tests have been carried out on the high velocity flow effects,
wave action and sudden draw down and Manning’s ‘n’
determination. These test results are available on request.
600mm min.
Filter Fabric
Keystone
Cap Unit
10-20mm crushed rock,
fill cores and voids of
Keystone units
Keystone
block
Nonwoven
filter fabric
Fig F6 — Typical Construction Detail — Keystone Seawall Application
Water level
150mm min.
Typical
1900mm
150 - 200mm
rip-rap
F8 July 2008 | BORAL MASONRY DESIGN GUIDE

Typical Terraced Wall Application Layout
When terracing walls, they are effectively being split into
sections. This is done for a number of reasons. For example, to
level off a sloping front or backyard, to increase the aesthetic
appeal of the garden and in some instances to reduce the single
wall heights where by they still act as gravity walls and thus
minimise the need for geogrid. In such instances, however,
the upper terrace wall can put pressure on the lower terrace if
the walls are too close together. Multiple terrace walls in close
proximity to each other, can have structural stability issues
related to the lower walls not having the capacity to carry the
loads developed by the upper walls.
Question:
How far apart do the terrace walls have to be to perform as
individual gravity walls?
Answer:
As a rule of thumb, the minimum distance between the wall
terraces must be at least 1.5 times the height of the lower wall.
H 2
BORAL MASONRY DESIGN GUIDE | July 2008
Keystone or Pyrmont wall
Example:
L = 1.5 x (H1)
L = minimum distance between terraces
Fig F7 — Typical Construction Detail — Terraced Wall Application
Queensland Book 4 F
If the lower gravity wall is 1.2m tall, then the minimum
recommended spacing between terraces is 1.8m. This rule
also applies to walls with more than two terraces. The
distance between any two terraces must be at least twice
the height of the lower adjacent terrace wall for multiple
terraces.
NOTE: This simple rule of thumb does not address global
stability issues where walls are built on steep slopes or over
poor soils of low friction strength. If these conditions exist,
then contact your engineer.
Question:
What if there isn’t enough room to space the terraces
according to this rule (1.5 x H1 minimum)?
Answer:
The wall can still be built, but the effect of the upper terrace
on the lower terrace and overall stability must be taken
into account when designing the walls. When the terraces
are close together, the design analysis may model the
structure as a single taller wall to account for the added load
from the upper terrace wall on the lower walls.
H 1
Cap unit
Keystone or
Pyrmont wall
F9

Queensland Book 4 F
Typical Fencing Application Layout
Fences can be incorporated into the Keystone Retaining Wall
System by placing fence posts into the Keystone cores or
behind the wall.
NOTE: The following recommendations are suitable for fences
with no wind loadings.
Fence posts should be embedded through a minimum of three
courses (600mm minimum) and then core filled with concrete.
Only those units with the fence posts need to be core filled with
concrete, the remaining filled with drainage material.
1824mm max.
Fig F8 — Typical Fencing Detail
Fence posts positioned behind the wall should be embedded
700mm minimum and encased in concrete.
When constructing a soil reinforced wall, the Geogrid may
be cut to allow for placement of fence posts as per the Geogrid
manufacturer specifications.
It is important that these walls be designed to accommodate any
additional wind loads from fencing (eg. extra embedment).
900mm
700mm
F10 July 2008 | BORAL MASONRY DESIGN GUIDE

Typical Railing and Barrier Application Layout
Railing, guard rail, and traffic barrier requirements for retaining
walls are not clearly defined in design codes nor are they
properly addressed in many site plans. Many times railings
and barriers are added as an afterthought which can become
a costly and logistical issue when no provisions are made in
the original retaining wall layout and site design. Guard’s
and barriers require a common sense approach by the site
designer considering the proximity of a wall structure to
people and traffic. Sufficient space must be reserved for such
installations.
150mm
1000mm min.
Load
BORAL MASONRY DESIGN GUIDE | July 2008
Queensland Book 4 F
It is important that these walls be designed to accommodate
any additional loading these guards and barriers may impose
on the Keystone wall.
Load Load
Typical
900mm
Additional Geogrid
layer turned upwards
and wrapped around
void former at 400mm
below ground level
900mm min.
Railing – offset Railing – offset
Load
Typical
800mm
Guardrail Traffic Barrier
Fig F9 — Railing and Barrier Details
Typical
900mm
F11

Customer Support New South Wales
Other Regional Sales Offices
NSW Clunies Ross Street, Prospect, 2148 T: (02) 9840 2333
F: (02) 9840 2344
231 Wisemans Ferry Road Somersby 2250 T: (02) 4340 1008
F: (02) 4340 1308
ACT 16 Whyalla Street, Fyshwick, 2609 T: (02) 6239 1029
F: (02) 6280 6262
Victoria Level 1 Port IT, 63-85 Turner Street, Port Melbourne, 3207 T: (03) 9363 1944
F: (03) 9363 6008
South Australia Main North Road, Pooraka, 5095 T: (08) 8262 3529
F: (08) 8260 3011
eBC 03812 July 2008
1. Stock colours Colours other than stock colours are made to order. Not all colours displayed in this brochure are available in all states.
(Contact your nearest Boral Masonry offi ce for your area’s stock colours.)
A surcharge applies to orders less than the set minimum quantity.
2. Brochure colours The printed colours in this Masonry Design Guide are only a guide. Please ask to see a sample of your colour/texture
before specifying or ordering.
3. Colour and texture variation The supply of raw materials can vary over time. In addition, variation can occur between product types and
production batches.
4. We reserve the right to change the details in this publication without notice.
5. For a full set of Terms and Conditions of Sale please contact your nearest Boral Masonry sales offi ce.
6. Important notice Please consult with your local council for design regulations prior to the construction of your wall. Councils in general
require those walls over 0.5m in height and/or where there is loading such as a car or house near the wall be designed and certifi ed by a
suitably qualifi ed engineer.
Technical Enquires
Specifier Line 1300 360 255
Internet www.boral.com.au/masonry
Orders, Product Samples and Sales Enquires
Queensland 62 Industrial Ave, Wacol, 4076 T: (07) 3271 9292
F: (07) 3271 1581
North Queensland:
Cairns 8 Palmer Street, Portsmith, 4870 T: (07) 4035 1888
F: (07) 4035 1208
Townsville 360 Bayswater Road, Garbutt, 4814 T: (07) 4725 6285
F: (07) 4725 6043
Mackay David Muir Street, Slade Point, 4740 T: (07) 4955 1155
F: (07) 4955 4130
® Heathstone and Pyrmont are registered trademarks of Boral Masonry Limited.
® Keystone and Gardenwall are each registered trademarks of Keystone Retaining Wall Systems, Inc.
under licence by Boral Masonry Limited. ABN 13 000 223 718
© Boral Masonry — all rights reserved 2004.