考虑应变软化的边坡稳定分析

Stability Analysis of the Slope Considering Strain Softening

在密砂、坚硬黏土及原状土的强度试验中,土试样常表现为应变软化,随着应变的增加其抗剪强度降低,并且发生渐进破坏。应用传统的极限平衡法,采用峰值强度作为计算参数进行稳定分析验算时,通常忽略土材料的渐进破坏过程,这可能会对边坡稳定评价带来不利影响。基于有限元极限平衡法,提出考虑应变软化的边坡稳定分析方法,并通过算例分析证明该方法的合理性。

In the laboratory, when dense sand, stiff clay, and undisturbed soil were subjected to strength tests, these soils experienced a pronounced strain-softening behavior. A progressive fail- ure in these materials was due to a reduction of strength produced by increasing strain. However, the standard soil test method provides that the material＇s peak strength is considered to be its fail- ure strength based on the relationship between stress and strain. Progressive strength failure in soils has been previously ignored during the analyses performed using the traditional limit equilib- rium approach on the basis of peak strength. In this paper, a new finite element limit equilibrium method is proposed in which strain-softening properties of the soil were assumed. And it was shown that this method can predict the stability of strain-softening soils for engineering purposes.