THE USE OF FRICTION-TRANSFER METHODS IN PREDICTION OF IN-SITU STRENGTH OF CONCRETE

An account of experimental and analytical work related to the newly developed friction-transfer method is presented. In addition to a literature survey on core testing, the results of compression tests on fourteen series of concrete cores and cubes with different characteristic strengths are compared with those of the friction-transfer method. For each mix design, three core tests were carried out, using 200mm cubes and 150mm cubes, for three friction-transfer and three compression tests. Finite element analysis of the friction-transfer method was also carried out and showed that the damage caused by this method was insignificant and confined to the partial core. Considering such factors as repeatability and reproducibility, (simplicity, speed, applicability under any site conditions by untrained operators), very low cost, easy interpretation and results, and good accuracy, this new method is recommended as a substitute for core testing, whenever the in-situ compressive strength of concrete is sought