考虑能量耗散的2级边坡参数反演分析

摘要

反分析是获得岩土工程强度参数的重要方法.基于2级边坡塑性力学极限分析,在Mohr-Coulomb破坏准则下,建立2级边坡容许速度机动场,分别推导2级边坡的重力功率及边坡内部能量耗散功率的表达式,并结合强度折减法,求得其安全系数.以某边坡工程为例,根据不同粘聚力c及内摩擦角ψ下的安全系数变化情况,得到安全系数为1时的c-ψ曲线,并据此进行参数反演.计算结果表明,此方法可靠有效.%Inverse analysis is an important method to obtain strength parameters of geotechnical engineering.Based on the analysis for plastic mechanics limit of the secondary slope and under the MohrCoulomb failure criterion,this paper establishes the allowable speed kinetic field of the secondary slope,derives expressions of gravity power of the secondary slope and energy dissipation power inside the slope,respectively and solves safety factor in combination with the strength reduction method.With some slope project as an example,the paper obtains the c-ψ curve when safety factor is 1 in accordance with changes of safety factor at different cohesive forces c and internal friction angles ψ,and conducts parametric inversion accordingly.The result of calculation shows that this method is reliable and effective.