关键词: 注浆材料, 裂纹缺陷角度, 类岩石试件, 单轴抗压强度, 破坏模式

Abstract: Epoxy resin and cement paste are chosen as grouting materials, uniaxial compressive tests are conducted on the specimens containing single grout-infilled flaw having different inclination angles. Experimental results show that grouting materials and flaw inclination angle have a significant influence on the uniaxial compressive strength and failure mode of rock-like specimens. The reinforcement effect of epoxy resin is better than that of cement paste, epoxy resin can effectively eliminate the stress concentration of the tips of the grout-infilled flaw. Whether the flaw is grouted with epoxy resin or cement paste, grouting has little improvement in uniaxial compressive strength(UCS) when the flaw inclination angle is very small ( <30°) or very large ( =90°), however, reinforcement effect is significant when the flaw inclination angle is 60°. For the specimens containing single flaw grouted with epoxy resin and cement paste, the failure path dose not cut through the grouting materials but cut through the interface between grouting material and model material. Sliding crack model is proposed. This model indicates that the UCS of specimens increases with increasing cohesion and friction angle of the interface between grouting material and model material. Different grouting materials have different improvement on the cohesion and friction angle of the interface, which is the reason why different grouting materials have different improvement on the UCS of specimens. This study will provide a theoretical frame for analyzing the influence of grouting materials and the inclination angle of flaw on the strength of rock mass in engineering projects.

Key words: grouting material, flaw inclination angle, rock-like specimens, uniaxial compressive strength(UCS), failure mode