AS 1012.25.1:2020 pdf Methods of testing concrete Method 25.1: Determination of the fibre content of plastic state concrete (wash-out test)
1 Scope
This Standard sets out the method for determining the fibre content of concrete that is in the plastic
state, by using a wash-out process.
A sample is taken from a concrete load, or from concrete made in the laboratory and compacted into a measure of known volume. The steel or synthetic fibres are washed out, separated and dried. The fibre content is determined from the mass of fibre and the measured volume of concrete.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document:
NOTE Documents referenced for informative purposes are listed in the Bibliography.
AS 1012.1, Methods of testing concrete, Method 1: Sampling of concrete
AS 1012.2, Methods of testing concrete, Method 2: Preparing concrete mixes in the laboratory
3 Terms and definitions
For the purpose of this document, the terms and definitions given in all referenced AS 1012 series
documents and those below apply.
3.1 may
indicates the existence of an option
3.2 shall
indicates that a statement is mandatory
3.3 should
indicates a recommendation
4 Apparatus and materials
4.1 Measure
4.1.1 General
The measure shall be made of metal not less than 3 mm thick, be watertight and be sufficiently rigid to maintain its shape with rough usage. The inside surface shall be smooth and free from corrosion. The rim of the measure shall be machined to a plane surface perpendicular to the axis of the cylinder.
NOTE The measure should be provided with carrying handles.The diameter of the measure shall be between 0.75 and 1.25 times the height.
For testing concrete with aggregates of nominal size not exceeding 40 mm, the capacity of the bowl
shall be not less than 5 L.
For testing concrete with larger aggregate, a larger bowl shall be used (e.g. for concrete with maximum 75 mm nominal size aggregate). A measure of capacity not less than 10 L shall be used.
4.1.2 Volume check
The measure shall be checked at a known temperature by determining the mass in kilograms of water required to precisely fill it. Filling shall be achieved by sliding a flat glass cover plate over the overfilled measure such that no air is trapped under the cover. The capacity of the measure shall be obtained by dividing the mass of water so determined by the unit mass of water at that temperature, e.g. 997.5 kg/m 3 at 23 °C.
When compacted as per this test method, the volume of the concrete sample (V c ) shall be the same
volume as that determined for the measure, expressed to the nearest 0.02 L.
4.2 Balance
A balance of sufficient capacity with a limit of performance as follows:
(a) For mass determinations greater than 2 kg, a limit of performance not exceeding ± 5 g with an
accuracy of at least 1 g.
(b) For mass determinations less than 2 kg, a limit of performance not exceeding ± 0.5 g
readable to 0.1 g.
4.3 Rod
The rod used for the compacting of concrete in the measure shall be a metal rod of 16 ± 1 mm in diameter,approximately 600 mm long and having at least one end tapered for a distance of approximately 25 mm to a spherical shape having a radius of approximately 5 mm.
4.4 Mallet
The mallet used in conjunction with the rod for compacting of concrete shall be fitted with a hard
rubber or hard plastics head of mass approximately 0.25 kg.
4.5 Scoop
A scoop, shovel or other receptacle used for sampling concrete, with a capacity of not less than 1 L.
4.6 Glass cover plate
A flat glass or plastic cover plate shall be used in the volume check of the measure.
AS 1012.25.1:2020 pdf Methods of testing concrete Method 25.1: Determination of the fibre content of plastic state concrete (wash-out test)
