掺污泥改性高水材料典型加载方式下的变形特征和力学响应

高水材料的掺杂改性有利于改善其物理力学性能、消纳废弃资源及降低经济成本,近年来成为采空区充填等领域的研究热点。针对典型加载方式下掺杂改性高水材料的变形特征及力学响应进行分析,结果表明:掺污泥改性高水材料在常规单轴加载试验和分级循环加卸载试验中受剪切破坏与劈裂破坏共同作用,慢速单轴加载试验中试样主要受剪切破坏作用;不同加载方式下,试样的压缩过程与普通岩石压缩过程相似,均可分解为五个阶段的组合:压密阶段、弹性阶段、屈服阶段、塑性阶段以及稳定阶段;与常规单轴压缩方式相比,慢速单轴加载方式与分级循环加卸载方式均会使得掺污泥改性高水材料抗压强度降低;增大加载速度会使掺污泥改性高水材料产生更高的弹性模量值,同时循环加卸载方式也具有提高掺污泥改性高水材料弹性模量的作用。

Deformation Characteristics and Mechanical Response of Modified High Water Material Mixed with Sludge under Typical Loading Methods

Doping is beneficial to improve the physical and mechanical properties of high water material, to assimilate waste resources and to reduce the economic cost, and it became a hot research topic in goaf filling fields in recent years. Analysis on the deformational characteristics and mechanical response of modified high water material mixed with sludge under typical loading methods was conducted. Results showed that the modified high water material mixed sludge was subject to shear and splitting failure in normal uniaxial loading and cyclic loading test, and the samples were mainly affected by the shear deformation in slow uniaxial loading test. Under different loading modes, the whole compression process could be decomposed into a combination of five stages: compaction stage, elastic stage, yield stage, plastic stage and stable stage. Compared with the normal uniaxial loading, slow uniaxial loading reduced the compressive strength of modified high water material mixed with sludge, and cyclic loading caused the reduction of compressive strength of the material as well. The elastic modulus of this mixed material would increase with the increasing loading speed, and cyclic loading could also improve the elastic modulus of the modified high water material mixed with sludge.