WANG Wei, WANG Bohao, ZHAO Yuntian, PAN Jianwen, JIN Feng
Cemented granular materials (CGM) are composed of densely packed particles bound together by a cement matrix that partially fills the interstitial pores which provides considerable stiffness to the material. This study investigated the mechanical behavior and acoustic emission (AE) response characteristics during uniaxial compression of an artificial cemented granular material made from high alumina ceramic beads combined with a self-compacting cement paste. The samples were fabricated using the rock-filled concrete technique without disturbing the granular backbone. The results show that the compressive strength is a linear function of the matrix volume fraction. Brittle fracture is the most significant mechanical behavior. Compaction in the linear-elastic regime is the dominant behavior in the pre-peak strength region with strain-softening accompanied by strain-hardening after the peak strength. The extent of the compaction phase linearly increases with the matrix volume fraction. However, the extent of the linear-elastic phase is independent of the matrix volume fraction. For the samples with little matrix material, an AE signal occurred when the material strength approached the peak value. The AE signals of samples with more matrix material mainly occurred in the initial stages of the elastic phase. The AE signals of samples with higher matrix volume fractions were found at the mid-term stage of the compaction phase and remained high until the samples failed. The results will help to further understand the mechanical behavior of cemented granular materials, and also provide an important reference for the studies of sandstone, conglomerate, rockfill concrete and grouted sands.
