scope:

This part of ISO 18650 specifies the procedure and requirements for examination of the mixing efficiency of batch-type and continuous-type concrete mixers as defined in ISO 18650-1. It is applicable to concrete mixers having a rated capacity greater than or equal to 70/50. The test consists of the determination of the variance of the mortar, coarse aggregate and air content, and the consistency of concrete mix samples, drawn after an assumed mixing time. Compressive strength is also tested. The measure of a concrete mixer's efficiency is the value of the variance of the above parameters, after the assumed mixing time.