The effect of aggregate size on strength and deformation of concrete

Conclusions

Increasing the granular composition of the aggregate increases the efficiency utilization of cement in concretes working in compression. At the same time, there is a reduction in deformation and an increase in Young's modulus and unit weight of the concrete. The tensile strength of the concrete is severely affected by increasing the size of the aggregate.

On increasing the maximum grain size to 120–180 mm, the reduction in tensile strength is 30–50% as compared with concretes with maximum aggregate size 20 mm. There is also a reduction in the elongation limit.

On increasing the aggregate size, homogeneity of the concrete deteriorates, and the values Rp and R_pb approach each other, even on specimens of the same cross-sectional dimensions.

When designing concretes for given strength and deformation properties, the coarseness of the aggregate is one of the most important technological parameters.