AS 1141.52 pdf download
AS 1141.52 pdf download.Methods for sampling and testing aggregates
4 Apparatus
Apparatus conforming to the relevant provisions of AS 1141.2 and the following shall be used: (a) Balance — A balance of sufficient capacity, with a limit of performance not exceeding ±5 g. (b) Base — A flat, rigid foundation on which to compact the specimen; for example, a concrete floor or concrete block of at least 100 kg mass. (c) Containers — Airtight containers, suitable for curing moistened test samples. (d) Datum bar — A metal bar approximately 200 mm × 20 mm × 10 mm dimensions.NOTE Regardless of the actual width and thickness dimensions, the longitudinal opposite faces of the bar are plane and parallel to within 0.1 mm. (e) Dishes — Metal dishes about 225 mm and 350 mm in diameter. (f) Equipment —Equipment for measuring test specimens that is accurate and readable to 1 mm; for example, a vernier gauge calliper. (g) Filter paper — 150 mm diameter coarse filter paper (optional). (h) Mixing apparatus — Including a bowl, trowel, spatula, and metal quartering plates about 400 mm by 125 mm and 200 mm by 125 mm. (i) Mould — A cube-type mould complete with plungers, guide moulds, cube-mould cramps and a parting tool (see Figure 1). (j) Oven — Thermostatically controlled, preferably with forced air circulation, capable of maintaining a temperature within the range of 105 °C to 110 °C. NOTE 1 Normally, drying is performed in an oven within the range of 105 °C to 110 °C, but when a method requires drying at different temperatures, the specified temperatures should be used. NOTE 2 Material may be dried to constant mass (see AS 1141.1 for the definition of constant mass) using alternative methods, such as microwave ovens, infrared lights or hotplates, provided tests have shown that these techniques do not disrupt or weaken particles to the extent that the property being measured changes.(k) Rammer — A metal rammer with a 50 mm diameter face and drop mass of 4.9 kg, equipped with a suitable device to control the height of drop to a free-fall of 450 mm, in accordance with AS 1289.5.2.1. (l) Sample dividers (riffle boxes) — With appropriate size openings (optional). (m) Sieves — 19.0 mm and 4.75 mm sieves. (n) Testing machine — A compression testing machine with a minimum capacity of 25 kN conforming to the requirements for Class B in AS 2193 and having two steel compression platens and a spherical seat conforming to AS 1012.9 and the ability to apply load at the rate given in Clause 7(c). (o) Vernier depth gauge — A vernier depth gauge, with a minimum scale length of 200 mm, that is accurate and readable to 1 mm.
5 Preparation of test portions
At least three test portions shall be prepared as follows: (a) Reduce the sample by quartering or riffling to provide at least 3 000 g of material that would pass a 19.0 mm sieve. Screen on a 19.0 mm sieve and weigh materials passing and retained on the sieve. Determine the amount of material retained as a percentage of the total (wet) mass. Discard material retained on the sieve. NOTE The exclusion of a large proportion of stone coarser than 19.0 mm may have a major effect on the unconfined cohesion determined, compared with that obtainable with the material as a whole. If specified, the same percentage of coarse material in the test portion as in the original sample can be maintained by replacing the material held on the 19.0 mm sieve with an equal mass of material passing the 19.0 mm sieve and retained on the 4.75 mm sieve; however, this will not necessarily produce the same result as an original test portion containing a high proportion of material coarser than 19.0 mm. (b) Thoroughly mix all material that passes the 19.0 mm sieve. (c) Obtain, by quartering or riffling, three test portions, each of about 1 000 g mass.
