裂面优化法稳定性分析——强度折减VS超重力

Stability analysis with discontinuity layout optimization:strength reduction vs gravity increasing

岩土结构如边坡及隧道的稳定性常用安全系数量化。安全系数有3种定义方式:抗力与滑动力之比、强度折减系数及超重力系数。针对后两种常用安全系数的定义,采用新颖的基于拓扑优化理论的极限上限分析方法:裂面优化法展开研究。提出了基于强度折减以及超重力策略的裂面优化目标函数,并考虑了多个算例展开数值研究。结果表明,裂面优化法计算过程高效,结果可靠,而强度折减策略与超重力策略获得的安全系数存在差异,两者差异与安全系数计算值以及摩擦角取值相关。

The stability of geotechnical structures such as slopes and tunnels is often quantified by safety factors.There are three standards for defining factor of safety:the ratio between resistance and driving forces;strength reduction factor and load increasing factor.Aiming at the commonly used strength reduction and load increasing factors,a novel upper bound limit analysis method based on topology optimization theory:discontinuity layout optimization(DLO)was used to study the obtained values considering different conditions.The target functions were proposed considering strength reduction and load increasing.Several numerical examples were tested,indicating the efficiency and reliability of DLO method.M eanw hile,the differences between the factors of safety of strength reduction and load increasing depend on the value itself and friction angle.