Director, Research and Development, Advice Pty Ltd., Croydon, VIC
Extensive research is being carried out in the area of concrete strength statistical control. Acceptance control plans are improved to reduce consumer's and producer's risks: the producer's risk consists in rejecting good-quality concrete, while that of the consumer, in accepting a substandard concrete. ACI 318 provides a low-level risk for a producer and a high-level risk for a consumer. It is demonstrated that the consumer's risk substantially decreases with the introduction of the quality assurance system.
The need to provide several acceptance criteria with various required probabilities of specified strength f′c and consumer's allowable risk in national codes is analyzed.
In addition, two procedures are given: the first consists in taking into account the actual concrete strength distribution, and the second, in rejecting gross errors.
Paper ID: CCA10121J