Abstract
The modulus of elasticity value is important from the design point of view but it is time-consuming in direct measurement. For normal concrete, it is found that the modulus of elasticity can be satisfactorily predicted from the compressive strength value, which is obtained very easily. In the case of two-stage concrete (TSC) there is no background information for evaluating its elastic modulus. The TSC differs from the conventional concrete in a higher percentage content of the stone aggregate. The aggregate is deposited directly into the moulds with point-to-point contact and a high flow grout is then introduced into the bottom of the mould. The contact stresses are transferred first through the stone skeleton and then after deformations of grains, also through the hardened grout. Therefore the properties of the TSC are more dependent upon the stone aggregate. Thus, the characteristics of the TSC in failure conditions are different from the normal concrete. The objective of this research was to present the influence of the grout proportions on the elastic modulus of the TSC observed during compressive tests.