滑坡推力与安全系数计算方法适用性研究

Applicability Study on Calculation Method ofLandslide Thrust and Safety Coefficient

基于传递系数显式解法(简称传统显式解法)推导了考虑桩反作用力的滑坡推力计算公式(即改进传递系数显式解法,简称改进显式解法);依托FLAC 3D软件平台建立模型,采用强度折减法对比分析了传统显式解法与改进显式解法计算的结果;研究了传统显式解法、改进显式解法,及传统隐式解法、改进隐式解法计算滑坡推力的适用性;分析了强度折减法与传统极限平衡法计算安全系数的区别。结果表明:由改进显式解法计算的滑坡推力大于由传统显式解法计算的;用改进显式解法计算的滑坡推力进行支护设计能够达到设计安全系数;采用强度折减法计算得到的滑坡推力与安全系数值均小于采用传统极限平衡法计算的;推荐采用改进的传递系数显式解法来计算滑坡推力,采用传统的传递系数隐式解法来计算滑坡安全系数。

Based on the explicit method of transfer coefficient(called conventional explicit solution for short),the calculation formula of landslide thrust considering pile reaction force was derived(that is,the improved explicit solution of transfer coefficient,which is abbreviated as the improved explicit solution).Then,the calculation model was established by using the FLAC 3D software platform,and the difference between the conventional explicit solution and the improved explicit solution was analyzed by the strength reduction method.The applicability of the conventional explicit solution,the improved explicit solution,the conventional implicit solution and improved implicit solution to calculate landslide thrust was discussed.The difference between the strength reduction method and the traditional limit equilibrium method to calculate the safety factor was discussed.The results show that the landslide thrust calculated by the improved explicit solution is larger than that of conventional explicit solution;using the landslide thrust calculated by the improved explicit method for support design can achieve the design safety factor;the landslide thrust and safety coefficient calculated by strength reduction method are smaller than those calculated by traditional limit equilibrium method.It is recommended that the improved explicit method of transfer coefficient is suitable for calculating landslide thrust,and the traditional implicit method of transfer coefficient is suitable for calculating the landslide safety factor.