Methods for determining the water and cement content of fresh concrete

TLDR: In this paper, the authors present several accelerated testing techniques for concrete quality control, which can be performed on hardened concrete cylinders or cubes in one or two days, as compared to the usual 28 days.

Abstract: Quality control of concrete has taken many forms in past years. The most traditional method has been to conduct compression tests on hardened cylinders or cubes. Although this has been a satisfactory method, it has one major deficiency, and that is the testing is done after the concrete has set. If the concrete does not meet specifications, then costly and time consuming reconstruction must take place. Several accelerated testing techniques have been developed recently, and although these tests are accomplished in one or two days, as compared to the usual 28 days, they still are conducted on hardened concrete. The ideal test, of course, is a test that can be conducted on the plastic or fresh concrete. It is these methods of analysis that are being discussed in this paper.