Collection
LS-Brochure-2016
LS-Brochure-2016
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
36 CE TESTING<br />
LONDON STONE | NATURAL STONE COLLECTION 2016 37<br />
Petrographic Description<br />
An assessment of macroscopic<br />
and microscopic characteristics.<br />
Properties such as rock group,<br />
particle shape, grain size and<br />
mineral composition will be<br />
established. The most pertinent<br />
information for the lay person<br />
would be the rock group i.e.<br />
sandstone, limestone slate, etc.<br />
Water Absorption at<br />
Atmospheric Pressure<br />
This test indicates how much<br />
water is absorbed by the material<br />
when fully immersed. The value<br />
represents the additional weight<br />
taken on by the sample as a<br />
percentage of the dry weight.<br />
Higher water absorption indicates<br />
more free space is available within<br />
the structure of the material.<br />
Compressive Strength<br />
This gives an indication of ultimate<br />
loading capacity for natural stone<br />
setts. Cubes have a vertical load<br />
applied until failure. The load<br />
required to crush the sample is<br />
the compressive strength. Natural<br />
stone setts with high compressive<br />
strength properties are well suited<br />
to high traffic areas.<br />
Flexural Strength<br />
This gives an indication of how<br />
much bending load a natural stone<br />
slab will take before it breaks.<br />
Products with high flexural strength<br />
are suitable for low and high traffic<br />
areas, whereas products with<br />
low flexural strength may only be<br />
suited to low traffic areas.<br />
Frost Resistance<br />
Frost resistance is measured by<br />
exposing samples to a specified<br />
number of freeze/thaw cycles.<br />
The samples are then visually<br />
inspected and flexural strength<br />
tested to establish if the process<br />
has affected performance.<br />
Products which are not frost<br />
resistant are not suitable for UK<br />
exterior use.<br />
Abrasion Resistance<br />
This test indicates how resilient a<br />
stone is to traffic, and how much<br />
wear will be tolerated. Samples<br />
are placed against a metal<br />
wheel and after a set number of<br />
revolutions the width of the groove<br />
formed is measured.<br />
Slip Resistance<br />
This is evaluated using Unpolished<br />
Slip Resistance Value (USRV).<br />
A pendulum test is performed,<br />
which imitates the action of a foot<br />
slipping over the surface of the<br />
finished surface. It is important to<br />
test materials dry and wet.<br />
The key testing requirements are EN 1431 EN1342<br />
EN 12407<br />
EN 13755<br />
EN 1926<br />
Petrographic description<br />
Water absorption at atmospheric pressure<br />
Compressive strength<br />
EN 12372 Flexural strength under concentrated load ( 3 - point )<br />
EN 12371<br />
EN 12371<br />
EN 14157<br />
EN 14231<br />
KEY TESTING REQUIREMENTS<br />
The Harmonised European standards which apply to the bulk of stone<br />
products supplied by London Stone are as follows. EN 1341 Slabs of<br />
natural stone for external paving - Requirements & test methods. EN 1342<br />
Setts of natural stone for external paving - Requirements & test methods.<br />
Frost resistance<br />
Post - 56 cycles freeze/thaw flexural strength<br />
Frost resistance<br />
Post - 56 cycles freeze/thaw compressive strength<br />
Abrasion resistance<br />
Slip resistance<br />
For advice and orders visit our inspirational showrooms, go online at www.londonstone.co.uk or call +44 (0)8442 251 915<br />
Check out London Stone and follow us on social media for hints, tips and advice.
Change language