充填体与围岩组合承压作用机理试验研究

Experimental study on combined pressure-bearing mechanism of filling body and surrounding rock

充填体作为地下矿山结构的组成部分,通过与围岩共同发挥承压作用,减缓围岩能耗及变形,从而有效控制围岩破坏的发展,维持矿山结构稳定。文章通过对充填体试件、围岩试件、充填体包裹围岩组合试件、围岩包裹充填体组合试件的力学试验研究,探索充填体与围岩组合承压作用模式及机理。试验结果表明:组合试件内外部组件均呈现剪切破坏模式;外部充填体包裹可对内部岩芯起到有效的支撑保护作用,并提高组合试件的单轴抗压强度;内部充填体的存在可使组合试件在破坏后出现阶段性的应力回升,并提高了组合试件的残余强度。研究结论解释了充填体可阻止岩石块体的刚性滑移、防止岩体在低应力条件下发生空间上的渐进破坏的作用机理,对于补充充填体与围岩相互作用理论研究具有一定的科学意义。

As a part of the underground mine structure, the filling body can reduce the energy consumption and deformation as well as the destruction development of surrounding rock to maintain the structure satiability. In this article, a series of mechanical testing on filling body samples, surrounding rock samples, samples of filling body wrapping surrounding rock, samples of surrounding rock zone filling body are taken to study the combined pressure-bearing mechanism of filling body and surrounding rock. The experimental results reveal that the failure modes of both the inner and outer components of the combined samples are the shear failure. The filling body could improve the uniaxial compressive strength of the inner rock components and make an effective supporting and protecting effects. Besides, the filling body can make the stress recovery and improve the residual strength of the combined samples. The conclusions explain why and how the filling body could help the rock mass to prevent the rigid sliding and the progressive failure under low stress condition. It has scientific significances to the theoretical study on the interaction mechanism between the filling body and the surrounding rock.