AS 2758.2:2021 – Aggregates and rock for engineering purposes Part 2: Specification for sealing aggregate
AS 2758.2:2021 – Aggregates and rock for engineering purposes Part 2: Specification for sealing aggregate.
AS 1141.24, Methods for sampling and testing aggregates, Method 24: Aggregate soundness—Evaluation by exposure to sodium sullóte solution
AS 1141.30.1, Methods for sum p1mg and testing aggregates. Method 30.1: Coarse aggregate quality by visual comparison
AS 1141.32, Methods for samplin,q and testing aggregates, Method 32: Weak particles (including clay lumps, soft and friable particlesJ in coarse aggregates
AS 1141.50, Methods for sampling and testing aggregates, Method 50: Resistance to stripping of cover aggregates from binders
AS 2758.0. Aggregates and rock for engineering purposes. Part 0: Definitions and classification
AS ISO/IEC 17025. General requirements for the competence of testing and calibration laboratories
3 Terms and definitions
For the purpose of this document, the terms and definitions in AS 2758.0 apply.
4 Aggregate classification
Aggregate requirements are specified for the following three aggregate classes:
(a) Class A — Premium quality aggregates suitable for freeways, heavily trafficked highways or pavements carrying a high volume of heavy vehicles.
(b Class B — Aggregates suitable for highways or main roads carrying medium traffic volumes, medium to lightly trafficked pavements, general parking areas and similar.
(c) Class C— Aggregates suitable for lightly trafficked roads.
NOTE For the purposes of the above classilicatlons—
(a) heavy traffic describes a road with greater than 2000 vehicles/lane/day;
(b) medium traffic describes a road with greater than 600 but less than 2 000 vehicles/lane/day; and
(c) light trail Ic describes a road with less than 600 vehicles/lane/day.
Unless it is practical to supply different classes of aggregate to the same profrct, specifiers should determine the required aggregate class based on the most severe requirements for any road to be sealed under works specification.
The works specification should also consider the type of vehicles when nominating any aggregate classification
5 Sampling
Where lot testing is referenced in Tables 1,2,3 and 4, a lot shall consist of not less than 5 samples.
Sampling of an aggregate shall be carried out en accordance with one of the methods described In
AS 1141.3.1.
NOTE 1 The frequency of sampling should be nominated in the works spedflcatlon or the supply agreement or as agreed with the supplier. In the absence of any of these documents, refer to AS 2758.0:2020 Appendix A for a sampling chcm.
NOTE 2 Reference samples may be taken during the course of supply antI retained for later testing.
7.4 Crushed particles of coarse aggregate
WhL!n determined in accordance with AS 1141.18, coarse aggregate that is derived from gravels or conglomerates shall consist of at least 75 % by mass of particles with at least two crushed faces.
NOTE With the exclusion of quarries in hard conglomerates, coarse aggregates derived from a hard rock quarrying process where all particles are crushed do nut require testing.
8 Durability
8.1 General
Not more than one ot the three sets ot methods for the assessment 01 aggregate durability shall be specified. These sets of methods represent those most commonly used in Australia and are provided In this document The set of methods specified should be the one which has been shown by local experience to be valid for rock sources likely to be used in the works.
NOTE All available tests and associated specification limits attempt to ensure adequate durability in service by measuring a change in properties over a short period ottime (varying from minutes to days). This necessarily involves the imposition olconditions (e.g. loadings.te,nperature, exposure to reagents) that are unlikely to be met in service, in order to accelerate the change. Some aggregates may behave differently in service than predicted by a given durabilify testing regime, These differences arise from the different responses of the rock mineralogy and texture to the actual conditions. Experience with the material in service is essential in interpreting the testing results.
If aggregate Is to be supplied from a source for which no cxpcrlcnce Is available with any of these assessment methods, the assessment procedure considered most appropriate for that source shall be specified. This decision will require some level of investigation before the appropriate procedure Is determined.
The durability assessment method options require the use of one of the following sets of test methods:
(a) Wet strength and wet/dry strength variation (see Clause 8.2).
(b) Los Angeles value and sodium sulfate soundness (see Clause 8.3).
c) Los Angeles value and unsound stone content (see Clause.8.4).