The Effect of Aggregate, Type and Quantity of Cement on Modulus of Elasticity of Lightweight Aggregate Concrete

This paper presents the results of experimental research on the effect of the lightweight aggregate, type and amount of cement on the values of the modulus of elasticity of lightweight aggregate concrete. Six different concrete mixtures were made to test if it is possible to replace recommended Portland cement with Portland composite cement, or to reduce the amount of cement and to obtain a satisfactory performance of the lightweight aggregate concrete. Values of the static and dynamic modulus of elasticity determined experimentally were analysed and then compared with the values obtained by FIP recommendation. In addition, for the five types of concrete, stress-strain (sigma-epsilon) curves were determined and analysed. It was concluded that there is a very good correlation between static and dynamic modulus of elasticity and very good match between the experimental and empirical results. The analysis of the values of sigma-epsilon curves led to the conclusion that type of cement does not significantly affect analysed properties, while the effect of the amount of cement cannot be neglected.