Effect of cement matrix on mechanical properties of cemented granular materials

Abstract

A well-defined cemented granular materials (CGMs) is created by filling cement matrix into a densely packed granular assembly without disturbing granular backbone, in which particles are held together by solidified and hence elastic matrix. In this study, a formula between strength and matrix volume fraction is theoretically deduced for CGMs, and it is verified through experimental tests. The CGMs samples, which are fabricated by filling high performance self-compacting cement paste into alumina ceramics beads assembly, are used to investigate the mechanical behavior and properties of CGMs under uniaxial compression. It can be found in the stress-strain curves that a nonlinear regime is remarkable and the extent of nonlinear section increases as the matrix content increases. In the post-peak region, a dominant strain-softening phase is followed by a transient strain-hardening phase. The strength, strain at failure and Young's modulus of CGMs get greater with the increase of matrix volume fraction. Interestingly, the peak strength of CGMs is relied on the particle-matrix adhesion and the matrix volume fraction. In additions, the uniaxial strain at failure and elastic modulus of CGMs are found to be a linear function of matrix volume fraction.