块石定向性特征对土-石混合体强度影响的数值模拟

Influence on the strength of soil-rock mixture made by the rock block orientation features based on numerical experiment

为了探讨土-石混合体的力学强度受块石定向性特征的影响,开发了二维椭圆块石集合体随机模型(2D Elliptic Block Collection Stochastic Model,简称EBCS^(2D)),并在此基础上进行了双轴压缩数值模拟。模拟结果显示土-石混合体的强度受块石定向性特征的影响,该影响规律与含石量显著关联。通过对各向异性屈服面曲线方程和数值模拟结果的拟合分析,验证了该屈服面曲线方程在表达土-石混合体强度方面的适应性。通过引入土-石相互作用单元的概念,阐明了在低、中、高3种含石量下,块石孤立作用和团簇作用交替主导,造成了块石定向性特征对土-石混合体力学强度的不同规律的影响。

This paper is to explore the influence on the strength of soil-rock mixture made by the rock block orientation features based on numerical experiment.The 2-D Elliptic Block Collection Stochastic Model(EBCS 2D)was developed and a series of bia-axial compression numerical tests were conducted.The result indicates that the strength of soil-rock mixture is affected by the rock block orientation features.This effect is highly related to the block proportion.The results of numerical experiments are fitting in an anisotropic yield surface equation,which proves the equation is suitable on the soil-rock mixture,describing the impact of the block proportion and orientation.The soil-rock interactive unit is introduced to explain the mechanism and result.The soil-rock mixture strength changing patterns to the block orientation features are dominated by isolated effect or clustered effect.The dominating effects vary with the block proportion.