AS 1141.54 pdf download

AS 1141.54 pdf download.Methods for sampling and testing aggregates
1 SCOPE
This Standard sets out the method for determining by visual examination the amount of foreign material in coarse aggregate produced from recycled concrete aggregate. The method is appropriate for material up to 75 mm nominal size and tests that fraction of the material retained on the 4.75 mm sieve. WARNING: CRUSHED CONCRETE AGGREGATE HAS BEEN KNOWN TO BE CONTAMINATED WITH ASBESTOS. WHEN SAMPLING FROM STOCKPILES OR PREPARING SAMPLES IN THE LABORATORY, THE CRUSHED AGGREGATE SHOULD BE DAMP TO PREVENT GENERATING AIRBORNE DUSTS. ON EXAMINATION, IF FIBROUS INORGANIC MATERIAL IS REVEALED OR IF THE AGGREGATE CONTAINS FLAT OR CURVED PARTICLES CLEARLY OF A MANUFACTURED ORIGIN (THAT IS SHEET OR PIPE FRAGMENTS) SAMPLING OR TESTING SHOULD BE SUSPENDED. ANY SAMPLE AND SAMPLE CONTAINERS SHOULD BE SEALED INTO HEAVY DUTY PLASTIC BAGS WITH MINIMAL ADDITIONAL HANDLING AND THE SAMPLES DEALT WITH IN ACCORDANCE WITH APPROPRIATE WORK, HEALTH AND SAFETY STANDARDS.
3 DEFINITIONS
For the purpose of this Standard, the definitions in AS 1141.1 and the one below apply. 3.1 Foreign material Any crushed material other than crushed concrete or any contaminant introduced during the demolition and crushing process.
4 TYPES OF FOREIGN MATERIAL
Foreign material is categorized as follows: (a) Type I or high density material such as asphalt, breccia, brick, ceramics glass, metal, sandstone, shale or slag (not blast furnace slag). (b) Type II or lowdensity material such as plaster, plastic, rubber, clay lumps and other friable material. (c) Type III or organic matter such as wood, vegetable matter, paper, cloth, paint and bitumen.
5 APPARATUS
The following apparatus conforming to the provisions of AS 1141.2, is required. (a) Balances—of sufficient capacity with a limit of performance not exceeding ±5 g for mass determinations >1 kg and ±0.5 g for mass determinations £1 kg. (b) Drying oven—capable of operating at 105°C to 110°C. (c) Sample dividers or quartering equipment. (d) Sieve—a 4.75 mm sieve. (e) Dishes, trays and brushes.
6 PREPARATION
A test portion shall be prepared as follows: (a) Obtain a sample of material using the appropriate procedure detailed in AS 1141.3.1. (b) Obtain, either by quartering or by the use of a sample divider, a subsample containing at least 2 kg and not more than 5 kg retained on a 4.75 mm sieve. (c) Handle in a manner that will avoid breaking up any clay lumps that may be present. (d) Record the wet mass of the subsample (M w ). (e) Remove all clay lumps and friable material from the subsample and record their mass (m c ). (f) Dry the sub-sample to constant mass in the drying oven. (g) Record the dry mass (M) of the sub-sample. NOTE: If this test is performed in association with a particle size analysis, it is permissible to conduct a washed procedure in accordance to AS 1141.11.1 at this point and retain all sieve fraction retained on the 4.75 mm sieve as the test portion.NOTE: The percentage of clay lumps is only an estimate because the clay will be at a higher moisture content compared with the moisture content of the subsample. The percentage clay lumps will be overestimated. If necessary, the procedures of AS 1141.32 may be followed on a separate subsample for a more accurate determination. If desired, the dry mass of the clay lumps may be estimated by determining the moisture content of the subsample and adjusting C above for moisture.
9 REPORT
The following shall be reported: (a) Source or sources of the product. (b) Nominal size of the product. (c) The sampling method used, as selected from AS 1141.3.1. (d) Date the product sample was taken. (e) Total percentage of each type of foreign material fraction, to the nearest whole number. NOTE: If required, a combination of classified fractions may be calculated and reported. (f) The percentage of clay lumps and friable material (either as a wet mass percentage or estimated dry mass percentage). (g) The number of this Standard, i.e. AS 1141.54.