Book Description

Three generations of the procedure were considered: Generation I: the original Kelly-Vail (KV) method developed by R.T. Kelly and J.W. Vail of the Greater London Council. Generation II: the CERL/KV method, developed by the U.S. Army Construction Engineering Research Laboratory (CERL). Generation III: the Corps of Engineers Concrete Quality Monitor (CE/CQM), also developed by CERL. The abilities of Generation II and III methods to help predict cement and water contents of a variety of concrete mixtures were determined in an extensive series of side-by-side laboratory tests. The tests evaluated the effects of sampling techniques and aggregate type. Variance techniques were analyzed to help establish accuracy statements and to compare the two methods and the utility of these methods as bases for predicting concrete compressive and flexure strength was assessed. Also, field and additional laboratory tests of the Generation III method were conducted to determine (1) how the Generation III method performed under field conditions and (2) the effects of selected common admixtures on the output of the chloride meter used in the Generation III method. The results demonstrated that the accuracies of Generations II and III were equivalent for identical test conditions and that aggregate characteristics affect the results of both cement content tests and both water content tests. It was also determined that actual water/cement ratios and water/cement ratios predicted on the bases of these methods may be used with equal accuracy for estimating 28-day concrete strength.