基于能量演化的胶凝砂砾石材料动损伤特征

Dynamic Damage Characteristics of Cement Sand and Gravel Materials Based on Energy Evolution

为更好揭示胶凝砂砾石材料的动态损伤特性,采用破碎耗散能定义了材料在动循环加载下的损伤变量,从能量角度探究材料的损伤演化特性。研究结果表明,随着应变增大,总能和耗散能增大,弹性能先增大再减小;随着围压和水泥含量的增加,材料的储能极限和最大耗散能呈非线性增加,屈服点耗散能占比逐渐增大,峰值点则不断减小,表明围压提高了材料抵抗侧向变形的能力与能量积聚的效率。胶凝砂砾石材料损伤变量表现出4阶段特征,损伤变量在裂纹扩展阶段增幅达到最大,在强度失效时平缓上升并趋近于1。

To better reveal the dynamic damage characteristics of Cemented Sand and Gravel(CSG)materials,the concept of breakage energy dissipation is employed to define the damage variable for CSG materials under cyclic loading.The evolution of damage characteristics of CSG materials under different confining pressures and cement contents is investigated from an energy perspective.The research findings indicate that with increasing strain,the total energy and dissipated energy increase,while the elastic energy first increases and then decreases.With the increase of confining pressure and cement content,the energy storage limit and maximum dissipated energy exhibit nonlinear growth.The proportion of dissipated energy at the yield point gradually increases,while the proportion of dissipated energy at the peak point decreases,indicating that the confining pressure improves the material’s resistance to lateral deformation and efficiency of energy accumulation.The damage variable of CSG materials demonstrates four-stage characteristics,with the maximum amplification occurring during the crack propagation stage,gradually rising and approaching 1 during strength failure.