含砾量对土石混合料力学特性影响离散元模拟

通过开展考虑砾石形状影响的双轴压缩试验离散元模拟，研究含砾量对密实土石混合料力学特性的影响。模拟结果表明:密实试样的应力应变关系表现出先硬化后软化的特征，含砾量越高软化效应越弱。随着含砾量增大，土石混合料的峰值强度呈现先减小再增加后减小的变化趋势，残余强度持续增大，剪缩到剪胀对应的体积应变先缓缓增加后加速减小，剪胀角则呈现减小趋势。通过颗粒移动特征及力链分布分析，发现当含砾量较低时，不能形成砾石骨架结构，含砾量对土石混合料强度影响较弱。

Discrete Element Simulation of Influence of Gravel Content on Mechanical Properties of Soil-Rock Mixture

The influence of gravel content on mechanical properties of compacted soil-rock mixture has been studied by discrete element simulation of biaxial compression test considering gravel shape. The simulation results show that the stress-strain relationship of the compacted sample exhibits the characteristics of hardening first and then softening, and the higher the gravel content, the weaker the softening effect. With the increase of gravel content, the peak shear strength of soil-rock mixture shows a varication trend of first decreasing, then increasing and then decreasing, and the residual strength continues to increase. The volume strain corresponding to shear shrinkage to shear dilation first slowly increases and then accelerates to decrease, and the shear dilatancy angle shows a trend of decreasing. Through the analysis of particle movement characteristics and force chain distribution, it is found that when gravel content is low, gravel frame structure can not be formed, and the influence of gravel on the strength of soil-rock mixture is weak.