Influence of limestone fillers and natural pozzolan on engineering properties of concrete

Abstract

The resonant frequency method is a non-destructive testing (NDT) technique for assessing building materials. It has been used to determine the dynamic properties of concrete; these are used in the design and control of structures, as they are key elements in materials dynamics. NDT is a reasonably good and reliable tool for measuring concrete’s properties, which in turn gives an exact indication of the evolution of the compressive strength. The influence of supplementary cementitious materials, such as limestone fillers and natural pozzolan, on the mechanical properties of ordinary concrete was investigated in this article. The elasticity moduli, compressive strength, and porosity were estimated in order to quantify the effects of various additions. The results show that the dynamic modulus of elasticity of concrete is strongly influenced by age. The inclusion of the additions has a significant influence on both the dynamic modulus of elasticity and the compressive strength. Concrete with additions gives a higher dynamic modulus of elasticity and generally exhibits, in the long run, higher compressive strengths than those found in reference concrete, except for those containing 30% of pozzolan. There is a good correlation between the dynamic modulus of elasticity and the compressive strength on the one hand, and the static and dynamic moduli, on the other.