CONCRETE CONSTRUCTION TABLE OF CONTENTS PAGE I ...

Polaris
Engineering
Standard
430.1
Rev.: 0
Page: 1 of 9
Date: 07/07/09
CONCRETE CONSTRUCTION
TABLE OF CONTENTS
PAGE
I. SCOPE 2
II. REFERENCES 2
III. MATERIALS 3
IV. FORMWORK 3
V. MIXING AND PLACING 4
A. Job Mixed Concrete 4
B. Ready Mixed Concrete 4
C. Placing Concrete 4
D. Construction Tolerances 5
VI. CONSTRUCTION JOINTS 7
VII. PAVING 8
VIII. FINISHING AND CURING 8
IX. COLORED CONCRETE FOR UNDERGROUND DUCT ENVELOPE 9
A. Material and Proportioning 9
B. Color Admixture 9
X. PUMPED CONCRETE 9
XI. WORK RECORDS 9
XII. DRAWINGS 9

Polaris
Engineering
Standard
430.1
Rev.: 0
Page: 2 of 9
Date: 07/07/09
CONCRETE CONSTRUCTION
I. SCOPE
This Standard covers requirements for construction of concrete structures and
foundations.
Where conflicts exist between this Engineering Standard and other POLARIS
Engineering Standards and/or applicable codes or regulations, the more stringent
requirement shall govern. All conflicts shall be brought to Client and/or Polaris
Engineering’s attention for resolution. Client and/or Polaris Engineering shall be the sole
arbiter of any conflicts.
II.
REFERENCES
This POLARIS Standard is to be used in conjunction with the latest revision of the
standards and codes listed below, unless specifically noted. The terminology "latest
revision" shall be interpreted as the revision in effect at the time of contract award. This
POLARIS Standard may reference specific sections of some of these codes and
standards. The revision of the codes and standards being referenced is noted below in
parenthesis. This information is provided to identify the subject matter being referenced.
Changes or exceptions made to the referenced code or standard shall apply to later
revisions as applicable.
A. POLARIS Engineering Standards:
1. 410.1 Concrete Roads and Paving
2. 430.2 Concrete Materials and Testing
3. 430.3 Concrete Reinforcing
B. American Concrete Institute (ACI) Codes and Standards:
1. 117 Standard Tolerances For Concrete Construction and
Materials (1990)
2. 304R Guide for Measuring, Mixing, Transporting and Placing
Concrete (2000)
3. 305R Hot Weather Concreting (1999)
4. 318 Building Code Requirements for Structural Concrete
(1999)
5. 325.9R Guide for Construction of Concrete Pavements and
Concrete Bases (1991)

Polaris
Engineering
Standard
430.1
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6. 347 Guide To Formwork For Concrete (2001)
C. American Society For Testing Materials (ASTM) Standards:
1. C33 Standard Specification for Concrete Aggregates (2001)
2. C94 Standard Specification for Ready-Mixed Concrete (2000)
3. C150 Standard Specification for Portland Cement (2000)
III.
MATERIALS
A. Concrete materials and concrete reinforcing are to be in accordance with design
drawings and the reference Standards stated above.
B. Air entraining or super plasticizer admixtures shall be provided in all concrete, in
accordance with POLARIS Engineering Standard 430.2. Client and/or Polaris
Engineering shall approve choice of admixture to be used.
C. Other admixtures shall not be used without written approval from the Client
and/or Polaris Engineering.
IV.
FORMWORK
A. Concrete forms shall conform to shapes, lines and dimensions of the members as
shown on design drawings. They are to be sufficiently tight to prevent leakage of
mortar, and be properly braced or tied together to maintain position and shape.
B. Provide 2 inches minimum clearance from top and sides of foundation to all
reinforcing bars (including ties) and 3 inches minimum clearance for bottom bars
from bottom of foundation.
C. Remove forms in such a manner as not to impair the safety and serviceability of
the structure. Formwork for columns, walls, sides of beams, and other parts not
supporting the weight of the concrete may be removed as soon as the concrete has
hardened sufficiently to resist damage from removal operations. In no case shall
supporting forms or shoring be removed until members have acquired sufficient
strength to support their weight and imposed loads safely. Sufficient strength for
beams, slabs and other items requiring support is defined as when test cylinders,
field cured along with the concrete they represent, have reached 2/3 of the
specified concrete strength.
D. The design and construction of the formwork shall be in accordance with ACI
347. This responsibility shall rest with the Construction Contractor or Concrete
Subcontractor.

Polaris
Engineering
Standard
430.1
Rev.: 0
Page: 4 of 9
Date: 07/07/09
V. MIXING AND PLACING
A. Job-Mixed Concrete
1. Job-mixed concrete shall be in accordance with ACI 304R.
2. Rotate the mixer at a speed recommended by the mixer manufacturer.
Continue mixing for at least 1-1/2 minutes after all materials are in the
mixer.
3. Mix all concrete until there is a uniform distribution of the materials and
discharge completely before recharging the mixer.
B. Ready-Mixed Concrete
Mix and deliver Ready-mixed concrete in accordance with ASTM C94.
C. Placing Concrete
1. Deposit concrete as near as practical to its final position to avoid
segregation of aggregates due to rehandling or flowing. The concrete
must be plastic at all times and flow readily into the spaces between
reinforcing bars. Water in excess of approved batch quantities shall not be
added for this purpose; however, appropriate admixtures approved by the
Client and/or Polaris Engineering may be used to improve flow.
2. After concrete placement has started, continue operation until the section
is completed except as prohibited or permitted by Section VI.
3. Do not drop concrete vertically more than eight feet. Use drop chutes for
higher lifts. The chute shall have a diameter of at least eight times the
maximum aggregate size and shall be positioned so that the concrete will
drop vertically.
4. Do not start placing concrete in supported elements (beams or slabs) until
the concrete previously placed in columns or walls is no longer plastic and
has been in place at least two hours.
5. All concrete shall be thoroughly consolidated by suitable means during
placement, and shall be thoroughly worked around the reinforcement and
embedded items and into the corners of the forms.
6. Install all embedded items such as anchor bolts, sleeves, inserts,
equipment bed and slide plates in their correct location and secure against
displacement.

Polaris
Engineering
Standard
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Date: 07/07/09
7. Concrete placed in hot weather shall conform to ACI 305R. Hot weather
is defined as any combination of high air temperature, low relative
humidity, and wind velocity tending to impair the quality of fresh
concrete.
8. Changes in temperatures of the concrete during placing and curing shall be
as uniform as possible and not exceed 5°F in any one hour period.
9. Do not use equipment made of aluminum or aluminum alloys for
pumplines, tremies, or chutes other than short chutes used to discharge
concrete from a truck mixer.
10. Do not retemper concrete with a slump too low for proper placement by
the addition of water at the placement location unless approved by the
Client and/or Polaris Engineering.
11. If placement is against hardened concrete, roughen the concrete surface to
an amplitude of 1/4 inch. Thoroughly clean and remove all loose material.
Thoroughly wet and remove standing water immediately before placing
new concrete.
D. Construction Tolerances
1. Tolerances for placement of reinforcement shall be in accordance with
ACI 117, Section 2.2.
2. Tolerances for concrete dimensions, locations and elevations.
a. Plumb (allowable variation) in the lines and surfaces of
columns, piers, and walls:
In any 10 feet
Total Height
1/4 inch
1/2 inch
b. Horizontal (plan) locations from specified coordinate lines or
dimensions
±1/4 inch
c. Elevations of supporting surfaces:
Top of grout
±1/16 inch
Top of rough concrete (under grout) ±3/8 inch
Top of concrete (no grout) ±1/8 inch

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d. Anchor bolt locations from coordinate lines of the foundation:
Without sleeves
With sleeves
±1/8 inch
±1/4 inch
e. Anchor bolt projections from final specified support elevation:
±1/4 inch
f. Cross sectional dimensions of columns, beams, walls, and slabs:
Up to 12 inches
Over 12 inches
+3/8, -1/4 inch
+1/2, -3/8 inch
g. Footings:
Horizontal dimensions:
Formed
Unformed
+2 inches, -1/2 inch
+3 inches
Misplacement or eccentricity of footing under pier (from
coordinate line):
Two (2) percent of the footing width in the direction of
misplacement but not more than 2 inches
Cross sectional thickness:
+5 inches, -5 percent
Level: +1/2 inch, -2 inches
h. Concrete structures linear building lines from the basic dimensions
in plan and related position of columns, walls and beams:
In any bay
In any 20 feet
Structure overall
±1/2 inch
±1/2 inch
±1 inch
i. Paving:
Elevations of high points and low points
±3/4 inch
Depressions between high spots measured below a 10 foot
straightedge:
Paving
Roads
1/4 inch
3/8 inch

Polaris
Engineering
Standard
430.1
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3. Reinforcing Steel
a. Variation in cover and depth:
Slabs
Foundations and Beam less than 24 inches
Foundations and Beams 24 inches or deeper
±1/4 inch
±3/8 inch
±1/2 inch
b. Variation in positioning lengthwise bars:
Straight bar
Hooked one end
±2 inch
+0 inch, -1/2 inch
c. Variation in spacing:
Slabs
Walls
Stirrups
±1 inch
+1 inch
+1 inch
4. Variation of Steps
a. In a flight of stairs:
Rise
Tread
±1/8 inch
±1/4 inch
b. In consecutive steps:
Rise
Tread
±1/8 inch
±1/8 inch
VI.
CONSTRUCTION JOINTS
A. Make and locate joints not indicated on design drawings so as not to significantly
impair the strength of the structure. Construction joints in elevated concrete
structures must have prior approval of Client and/or Polaris Engineering. Where
a joint is to be made, roughen the concrete surface to an amplitude of 1/4 inch.
Thoroughly clean and remove all loose material. Thoroughly wet and remove
standing water immediately before placing new concrete.
B. A delay, at least until the concrete is no longer plastic in columns or walls, must
occur before beams, girders, or slabs are supported thereon (see Section V.C.4).
Place beams, girders, brackets, column capitals and haunches for elevated
structures monolithically with the floor system.

Polaris
Engineering
Standard
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C. Locate construction joints in elevated floors near the middle of the spans of slabs,
beams, or girders. If a beam intersects a girder at this point, offset the joint in the
girder a distance equal to twice the beam width and provide adequate shear
reinforcement.
VII.
PAVING
A. See design drawings for soil preparation.
B. Slab thickness, reinforcement, load transfer dowels, and location and type of
joints shall be as shown on design drawings. Material and workmanship shall
conform to ACI 325.9R, except that wood side forms may be used, instead of
metal, if the finishing of the slab is done by hand or light machine methods.
C. Finish concrete by striking-off and consolidating, longitudinal floating, straight
edging and either brooming or belting.
D. Saw cut contraction joints as soon as concrete has attained sufficient consistency
to support the required equipment and before random cracking occurs, but no later
than 8 hours after placement.
VIII.
FINISHING AND CURING
A. All concrete surfaces shall be true and even after removing forms. Repair poor
joints, voids, stone pockets, tie holes or other defective areas. All exposed
surfaces, except those surfaces to be grouted, shall be sack-rubbed or honed to
provide a smooth and uniform finish on all above-grade surfaces extending from
6” below grade to finish elevation.
B. Consolidate, screed, and float floor slabs and paving to slopes and elevations as
shown on design drawings. Perform two steel trowelings to produce a hard, dense,
smooth surface finish. Provide a non-slip surface by brushing or brooming the
freshly troweled surface.
C. Maintain concrete in a moist condition for at least the first 7 days after placing;
maintain, high-early- strength concrete for at least the first 3 days after placing.
Other curing methods and periods may be used if the specified strengths are
obtained.
D. Chamfer exposed edges 3/4 to 1 at 45 degrees.
E. Concrete surfaces to receive grout and interfaces between new and previously
hardened concrete shall be clean and free of laitance and shall be roughened by
hand held chipping gun to provide a full amplitude of approximately 1/4 inch

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Engineering
Standard
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Date: 07/07/09
F. Slabs for skid foundations, transformer foundations or any foundation not
requiring grout shall be poured smooth, true and level. The top surface tolerance
shall be within plus or minus 1/8 inch in any 10 foot dimension from the specified
elevation.
IX.
COLORED CONCRETE FOR UNDERGROUND DUCT BANKS
A. Materials and Proportioning
1. All colored concrete shall have specified compressive strength of 3,000
psi at 28 days. Maximum aggregate size shall be 3/8 inch.
2. Mix concrete for at least ten minutes after color has been added.
B. Color Admixture
All concrete for underground electrical conduit envelopes shall be colored RED,
using 12 pounds of red oxide color per cubic yard of concrete.
X. PUMPED CONCRETE
A. Concrete may be pumped to the forms in accordance with this Standard.
B. Submit the proposed mix designs for each class of concrete to be pumped,
including all necessary background data of test results to the Client and/or Polaris
Engineering for authorization to proceed.
C. Take all slump and cylinder test samples from the end of the discharge line.
XI.
WORK RECORDS
A. In order to provide permanent work records and office review, the Contractor's
Field Superintendent or other designated representative shall keep a record of the
concrete work including dates, location, the quality and quantity of concrete
materials, the mixing and placing of concrete, curing conditions, and general
progress of the work. Unless otherwise directed, mail this record periodically
throughout the job to the Client and/or Polaris Engineering.
B. When the temperature rises above 100 o F, include a complete record of the
temperatures and protection given to the concrete while curing.
XII.
DRAWINGS
This Standard is supplemental to design drawings and, should any conflict occur, the
more stringent requirement will govern.