不同含石量土石混合体抗剪强度分形演化特征

Fractal evolution characteristics of shear strength of soil-rock mixture with different stone content

针对土石混合体抗剪强度及强度指标的变化特征,研究含石量与材料抗剪强度及强度指标的变化关系,建立混合土体抗剪强度的定量变化模型。研究结果表明:根据分形几何理论研究试验试件的分形特征,得到含石量与平均分形维数的演化特征,分析混合土体的细观特征;混合土体存在最优含石量,约为50%,其抗剪强度及强度指标随着含石量的增加而增加,粗颗粒构成土体骨架,细颗粒提高密实度,粘聚力敏感度高于内摩擦角;混合土体抗剪强度及强度指标与含石量、平均分形维数呈现线性函数变化,在最优含石量范围内,随着含石量的增加而线性增大,随分形维数的增大而线性减小。

Aiming at the variation characteristics of the shear strength and strength index of soil-rock mixture,the relationship between the stone content and the shear strength and strength index of the materials is studied,and a quantitative variation model of shear strength of mixed soil is established.The study results show that according to the fractal geometry theory,the fractal characteristics of the test specimens are obtained,and the evolution characteristics of the stone content and the average fractal dimension are obtained,and the mesoscopic characteristics of the mixed soil are analyzed.The optimal stone content exists about 50%,and the shear strength and strength index of the mixed soil increase with the increase of the stone content.The coarse particles constitute the soil skeleton,the fine particles increase the compactness,and the cohesive force sensitivity is higher than that of the internal friction angle.The shear strength and strength index with the stone content and the average fractal dimension show a linear function change.In the range of the optimal stone content,they increase linearly with the increase of the stone content,and decreases linearly with the increase of the fractal dimension.