中文摘要：

尾矿强度参数是影响尾矿坝体稳定分析的关键因素。基于室内尾砂三轴加载试验成果,对高应力条件下尾砂非线性强度特性予以研究。试验结果表明:高应力尾砂的三轴固结不排水剪切曲线具有明显软化特性,曲线软化程度随着围压的增大而增大。根据三轴应力-应变曲线建立了描述尾砂应变软化现象的改进双曲线模型,采用二次抛物线型、幂函数型的包络线描述强度特征的非线性。对比结果表明,幂函数型Mohr强度准则作为高应力条件下尾砂破坏的强度判据,具有较高精度。等效法向应力与内摩擦角正切值的函数关系表明,高应力条件下尾砂的内摩擦角不是一个定值,而具有幂函数型非线性特征。

英文摘要：

The tailings strength parameters is the key factor that affects the analysis of tailings dam stability.Based on triaxial tests under high stresses, the nonlinear strength property of tailings was validated.The results showed that the triaxial consolidation undrained shear curves had obviously softening characteristics, and the degree of strain softening increased as the stresses increased.According to triaxial stress-strain curves, an improved hyperbola model was set up for describing the phenomenon of tailings sand strain softening.The quadratic parabolic and power exponent function of envelope lines were adopted to describe the nonlinearity of strength characteristics, and the comparison results showed that the power exponent function of Mohr envelope had high precision as the criterion of breaking strength of tailings sand under high stresses.The function of equivalent normal stress and tangent value of internal friction angle indicated that the internal friction angle of tailings sand under high stresses was not a fixed value, but had nonlinearity characteristics of power exponent function.