Re: No-Fines Concrete Block.
A) Mass per Unit Volume – Rapid Measuring Method.
AS.1012.12.1 (cored specimens)
The result of 2140 kg/m3 is about 90 to 93% of what would be expected of a normal dense cement concrete and about
140 kg/m3 greater than the maximum generally nominated for a light weight concrete.

B) Water Permeability (Falling Head Laboratory Permeameter)
R.T.A. (NSW) T377 (cored specimens).
The results of 2.8 and 2.4 x 10-3 m/sec (2.8 & 2.4 x 10-1 m/sec) provides a classification of ‘medium degree of permeability’
(as per Soil Mechanics, Lambe & Whitman) identifying the concrete as having a similar permeability to that of a free draining sand.

C) Compressive Strength. AS1012.14 & 9 (cores specimens).
The test results of 22.0, 25.5 & 23.5MPa are higher than what is generally expected on no-fines concrete, that being between 10 & 20MPa.

D) Flexural Strength (Modulus of Rupture)
AS1012.11 (sawn specimens)
The results of 4.3 & 4.3MPa are considerably higher than what would be expected when considering the compressive strengths. This could be reflecting the value of incorporating fibre in the mix.
An appreciation of the flexural strength result can be gained by comparing the minimum concrete strengths required for a N.S.W. RTA Plain Base Concrete for main roads i.e. Minimum Compressive Strength of 35MPa with a Minimum Flexural Strength of 4.5MPa.

E) Indirect Tensile Strength.
AS1012.14 & 10 (cored specimens)
The results of 2.3 & 2.1MPa appear to reflect the compressive strength (about 10 to 1 ratio). The incorporation of the fibre may not have provided any tensile strength benefit.