In situ estimation of hardened concrete strength. Application to concrete placed in prestressed beams made at factory

Abstract

Application of some destructive or non destructive test of hardened concrete to estimate his commpressive strength, has been realised mainly in laboratory conditions. The experimental research that we have developed, has been coneected, on the one hand, with the concretes normally placed in reals building structures and, on the other hand, with those placed in prestressed beams made in a central factory. The reults has been analysed separately according the two levels of concrete strength. In this paper we have selected the results obtained testing the pretessed beams. The tests were carried out in a central factory of PACADAR, near to Bareclona, and in the laboratory of the ""Instituto Técnico de Materiales y Construcciones"" (INTEMAC) in Barcelona.