Quality assessment of mixed concrete in Saudi Arabia

Abstract

Currently there is a trend of eliminating truck mixing mechanism of concrete production from major construction contracts in Saudi Arabia. Such a shift is liable to produce far reaching effect on concrete industry in the Kingdom. This paper presents an experimental study of strength and uniformity aspects of the concrete produced by the truck mixing mechanism. The experimental work comprises strength tests according to BS 5328 and uniformity tests according to ASTM C94 and BS 3963. Results indicate that, with adequate control on mixing performance factors such as mixing time and drum speed, the truck mechanism complies with strength and uniformity requirements. The paper suggests improvements in test procedure to enhance the uniformity of concrete produced by the truck mixing mechanism and exercise control on operator performance so that strength variability can be reduced.