Mixing of Concrete and its Testing Methodology

We have seen various occasions where different performance characteristics of concrete in a structure are tested. In mostly cases, an estimate of strength of concrete in the structure is needed, other aspects like overall quality, uniformity etc. also becomes important in others. At present the direct test used mainly as a basis of quality control is compression testing of cubes, cylinders etc. and it represents the potential strength of the concrete used in the structure. The main parameters determining the qualities of concrete are its composition of mix, degree of compaction and curing. However, the methods of compaction and curing usually are different for the cubes and the structural members as quality control in laboratory is better that quality control in field. Due to this variation in quality control, results obtained on cubes may not truly represent the quality of concrete in the structure. Hence the use of Non-Destructive Testing on the newly constructed structure becomes necessary.