基于对数螺旋破坏机制的三维边坡稳定性分析

为研究三维边坡在对数螺旋破坏机制下的稳定性,基于极限分析上限法提出了非相关联流动法则下的速度场及安全系数的求解方法,可有效的解决相关联法则中摩擦角过大可能导致速度场不收敛的问题。基于Michalowski构建了考虑体积应变的均质三维边坡的对数螺旋线破坏机制,并利用MATLAB编制计算程序计算不同内摩擦角φ、不同边坡倾角β工况下边坡的稳定系数,分析内摩擦角、边坡倾角对稳定系数和破坏模式的影响规律,引入强度折减技术计算边坡安全系数,通过与Michalowski方法对比发现计算结果接近。研究结果表明:在三维边坡对数螺旋破坏机制下相对于一定宽度的边坡适用,且经过计算稳定系数符合规律。研究成果为边坡的设计计算提供参考。

Three dimensional slope stability analysis based on logarithmic spiral failure mechanism

In order to study the stability of three-dimensional slope under logarithmic spiral failure mechanism，based on the upper limit method of limit analysis，the solution method of velocity field and safety factor under the non-associated flow rule is put forward，which can effectively solve the problem that the velocity field may not converge due to excessive friction angle in the associated rule． Based on Michalowski，the logarithmic spiral failure mechanism of homogeneous three-dimensional slope considering volume strain is constructed，and the calculation program is compiled by MATLAB to calculate the slope stability coefficient under different internal friction angles φ and slope inclination angles β． The influence of internal friction angles and slope inclination angles on stability coefficient and failure mode is analyzed，and the strength reduction technology is introduced to calculate the slope safety factor． Compared with Michalowski method，the calculation results are close to each other． The results show that the logarithmic spiral failure mechanism of three-dimensional slope is applicable to slope with a certain width， and the stability coefficient is in accordance with the law after calculation． The research results provide reference for slope design and calculation．