Specifying Pavers for Commercial Application

Technical information

The following tests are to be considered when specifying pavers for commercial use:

  • Breaking Load in accordance with AS/NZS 4456.5.
  • Dimensional Deviation in accordance with AS/NZS 4456.3.
  • Slip Resistance in accordance with AS/NZS 4586.
  • Abrasive Resistance in accordance with AS/NZS 4456.5.
  • Salt Attack Resistance in accordance with AS/NZS 4456.10.

Breaking Load

This test measures the force needed to break a paver in half. The paver is supported on two beams and the force is applied by another beam in the centre. The results of this test are reported in kilonewtons (kN). They're a measure of the paver's ability to resist the stresses of handling, transporting and laying, and the loads likely to be encountered in service. Pavers with a breaking load of 2 kN or more are deemed to be strong enough to be transported and laid. Higher strengths (5kN and up) are needed for driveways, roads, etc. Normally the breaking load test is done on a sample of 10 pavers of the same size.

The breaking load test can also be used to measure the flexural strength of the material the pavers are made from (concrete, stone, fired clay), which can then be used to predict the breaking load of pavers of different dimensions. For example, how much stronger will a paver that's twice as thick be?

Dimensional Deviation

Often clients want to know how much variation there is in the size of our pavers. Consistency of dimensions is important whenever patterns or straight lines need to be maintained in a paved area, particularly when pavers are butted up against one another.

Under this standard test, 20 pavers can be either measured individually for length, width and thickness, or they can be placed side by side, end to end, etc and their cumulative dimensions measured.

MAXIMUM DIMENSIONAL DEVIATIONS DETERMINED FOR PAVERS AND FLAGS BY INDIVIDUAL MEASUREMENT

Category

Work dimensions, mm

Plan

Height

Standard Deviation

Mean

Standard Deviation

Mean

DP0

No requirement

DPB1

2.0

±3.0

3.0

±2.5

DPB2

2.0

±2.5

0.0

±2.0

DPB3

Values declared by supplier or by agreement between supplier and purchaser

DPB4

1.5

±2.0

2.0

±2.0

Slip Resistance

The standards allow the use of two different types of rubber slider with selection being based on the location and roughness of the surface.  A rubber slider known as 'Slider 96' (previously known as '4S') is normally used when testing polished or light to moderately textured surfaces. More coarsely textured surfaces may be tested with a 'as 'Slider 55' slider (also known TRL). The Slider 96 simulates a standard shoe sole and is relatively hard rubber typical of dress shoe soles. The TRL slider is a softer rubber compound originally designed to simulate tyre rubber but can also be simulate softer shoe soles or even bare feet.

Pendulum Classification

BPN Range

Location Example for V to Z classifications according to HB197:1999

AS 4586-2013

AS/NZS 4586-2004

Slider 96

Slider 55

P5

V

> 54

>44

External ramps

P4

W

45 – 54

40 - 44

External colonnade and walkway

P3

X

35 - 44

35 - 39*

Shopping centre – food court

P2

Y

25 – 34

20-34*

-

P1

Z

< 25

<20*

Lift lobbies above entry level

P0

-

<12

-

-

Abrasive Resistance

Pavers are subjected to abrasive wear on their top surface when in use, typically from foot traffic and also vehicular traffic.

The test for abrasion resistance involves pounding the pavers surface with hundreds of steel ball bearings. Sixteen pavers are fixed to the outside of a drum containing the ball bearings, and as the drum rotates, the ball bearings tumble and roll against the pavers through round holes in the drum. After an hour, the pavers are weighed to measure the mass loss, which is then converted to a volume loss and reported as the abrasion index.

Pavers with an abrasion index of 3.5 or less are considered suitable for high-volume pedestrian traffic (eg shopping centre entrances & pedestrian malls). Up to 5 is alright for roads and low-volume public footpaths, and for domestic driveways around 7 is acceptable.

Salt Attack Resistance

How resistant a paver is to the effects of salt crystallisation depends on things like the porosity of the paver and the strength of the material the paver is made from.

Pavers may be classed as Exposure Grade if they either have a history of coping with a salty environment, or have passed a laboratory test which simulates such conditions. This test involves putting small segments of paver through a series of 40 cycles of alternate soaking in a salt solution, then drying in an oven. If the specimens survive the 40 cycles with less than a specified loss in mass, they've passed the test.

SALT ATTACK RESISTANCE GRADE

Salt attack resistance grade

Requirements/Description

Exposure

(a) Supplier's experience, according to which it is possible to demonstrate that the product has a history of surviving under saline environmental conditions similar to those existing at the site considered.

or

(b) <0.4 g mass loss in 40 cycles in AS/NZS 4456.10.

General Purpose

(a) Supplier's experience, according to which it is possible to demonstrate that the product has a history of surviving under non-saline environmental conditions similar to those existing at the site considered.

or

(b) <0.4 g mass loss in 15 cycles in AS/NZS 4456.10.

NOTE: Where pavers or flags may be subject to chemical/environmental exposure (e.g., marine areas, swimming pools, thermal pools, etc.), it is recommended that they be, as a minimum, 'exposure grade'.

MINIMUM REQUIREMENTS FOR DIMENSIONS, BREAKING LOAD AND ABRASION RESISTANCE

Pavement applications

Minimum characteristic breaking load*                kN

Work size minimum thickness                    mm

Dimensional deviation category

Maximum abrasive resistance (mean abrasion index)

Pavers

Flags

Pavers

Flags

Pavers

Flags

Relevant Australian Standard

AS/NZS 4456.5

NA

AS/NZS 4456.3

AS/NZS 4456.9

Residential

Pedestrians only (e.g., paths,
patios and outdoor areas)

2

5

40

40

DP0

DPA1 or DPB1

Not required for residential pavers

 

Pedestrian and light vehicles
only (e.g., driveways, parking
spaces, and the like)

3

7

40

50

DPA1 or DPB1

DPA2 or DPB2

Not required for residential pavers

Pedestrian and commercial
vehicles

5

7

60

60

DPA1 or DPB1

DPA2 or DPB2

Not required for residential pavers

   

             

Pedestrian traffic volume

             

Low

Medium

High

Public Space

Pedestrians only **

2

5

40

40

DPA1 or B1

DPA1 or B1

7 ¥

5.5

3.5

Pedestrian and light vehicles
only

3

7

50

50

DPA2 or B2

DPA2 or B2

7 ¥

5.5

3.5

Pedestrian and commercial
vehicles

5

***

60

***

DPA2 or B2

DPA2 or B2

7 ¥

5.5

3.5

Trafficked
segmental pavers

Minor and residential

6

NA

60

NA

DPA2 or B2

NA

NA

Local access

6

NA

60

NA

DPA2 or B2

NA

NA

Collector

6

NA

76

NA

DPA2 or B2

NA

NA

 

*      At 28 days for concrete products only                                                                                                                   

**    Where cleaning of pavers and flags is undertaken by mechanical means or where prevention of vehicle entry cannot be guaranteed, the minimum recommended pavers and flags are the 'Pedestrian and light vehicles only' for such pavement applications.                                                                                                                      

*** Flags should be specifically designed for each application.                                                                                                                      

¥     Alternative means for demonstrating compliance with the performance requirements are given in Appendix B on AS/NZS 4455.2:2010