基于分形理论的土石混合体强度特征研究

 从土石混合体的非线性特性出发，应用分形几何理论研究土石混合体的强度特征。通过大型三轴试验，对不同粒度分维不同围压下土石混合体的应力–应变特性、强度参数特征及峰值强度特征进行分析；并讨论强度参数、峰值应力差与粒度分维值的关系。结果表明：土石混合体的应力–应变特性相似于岩石典型应力–应变曲线；不同粒度分维的土石混合体强度包线总体呈线性性质，粒度分维值对强度影响很大，其与抗剪强度的关系近似一抛物线；对于只具一维分形的土石混合体具有最大的密实度和抗剪强度，属最优级配土石混合体，并分析产生这一现象的原因。

STUDY OF STRENGTH PROPERTIES OF EARTH-ROCK AGGREGATE BASED ON FRACTALS

Starting from nonlinear characteristics of earth-rock aggregate，fractal geometry theory was used to study earth-rock aggregate strength properties .The stress-strain relationship，strength parameter characteristics and peak strength were analyzed under different confining pressures and fractal dimensions of granularity using large-scale triaxial tests. Relationships among strength parameters，peak stress difference and fractal dimensions of granularity were also discussed. Test results indicate that stress-strain properties of earth-rock aggregate were similar to stress-strain curves of typical rock，and strength envelope under different fractal dimensions of granularity was linear approximately. The earth-rock aggregate with 1D fractal had the largest compact ability and shear strength，which belonged to optimal gradation earth-rock aggregate and the reason was analyzed as well.