AS 2758.2 pdf download

AS 2758.2 pdf download.Aggregates and rock for engineering purposes
1  Scope
This document provides a basis for specifying requirements for aggregates intended for use in sprayed bituminous surfacing. The requirements relate to quality of rock and other properties of coarse aggregate. A coarse aggregate may be produced from rock, gravel, metallurgical slag or suitable synthetic materials. This document is intended for use by — (a) federal, state and local government authorities (whether or not they are specifiers); (b) consultant engineers (whether specifiers or not); (c) suppliers and purchasers of asphalt aggregates; (d) testing authorities; (e) quality system certifiers and accreditation authorities; and (f) educational organisations.
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 classifications— (a) heavy traffic describes a road with greater than 2 000 vehicles/lane/day; (b) medium traffic describes a road with greater than 600 but less than 2 000 vehicles/lane/day; and (c) light traffic describes a road with less than 600 vehicles/lane/day. Unless it is practical to supply different classes of aggregate to the same project, 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 in accordance with one of the methods described in AS 1141.3.1. NOTE 1  The frequency of sampling should be nominated in the works specification 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 scheme. NOTE 2  Reference samples may be taken during the course of supply and retained for later testing.
6  Testing
Testing of aggregates shall be carried out in accordance with the relevant requirements of the applicable methods. Laboratories that perform the tests outlined in this document shall meet the requirements of AS ISO/IEC 17025. The testing requirements and specified limits for all sealing aggregates are prescribed in Clauses 5 to 11. NOTE  A number of requirements in this document are fundamental and this specification provides a single test method and limits for these properties. Alternative test procedures and limits are presented for the determination of both shape and durability. For these properties, it is recommended that the test procedure and limits that are particular to the geographic area in which the aggregate source is located should be used in specifying supply.
7  Dimensional requirements
7.1  Grading requirements for aggregates When determined in accordance with AS 1141.11.1 or AS 1141.11.2, each lot shall conform to the grading envelopes given in Table 1.lists the common nominal aggregate sizes that are typically produced and in-line with with coarse aggregates specified in AS2758.1. However, the works specification may include other nominal sized aggregates where they are locally available and considered appropriate for a particular application. 7.2  Particle shape of aggregates The shape of aggregate particles shall be determined by one of the following methods: (a) Particle shape — When determined in accordance with AS 1141.14, the proportion of misshapen particles in the fraction of coarse aggregate retained on the 9.5 mm test sieve, using a 3:1 ratio, shall not exceed 10 % and using a 2:1 ratio shall not exceed 35 %. (b) Flakiness index — When determined in accordance with AS 1141.15, the flakiness index of aggregate for each class shall not exceed 35 %.