考虑滑带强度分区的基覆式滑坡抗滑桩设计推力算法-《高速铁路技术》

文章信息/Info

Title:: Calculation Method for Design Thrust Force on Anti-slide Pile for Bedrock-covered Landslide Considering Strength Partition of Landslide Zone

Author(s):: YAN Yuping; XIAO Shiguo; Southwest Jiaotong University, Chengdu 610031, China

Keywords:: bedrock-covered|landslide|anti-slide pile|thrust force|strength of landslide belt|imbalanced thrust force method

摘要:: 为了在抗滑桩设计中充分考虑坡体滑带上各点所处的峰值与残余抗剪强度状态的差异性，针对基岩-覆盖层式滑坡，文章将数值模拟与极限平衡法相结合，基于弹塑性有限元分析法获得抗滑桩加固后坡体的应力场，根据滑带上一点剪应力与抗剪强度大小关系，同时考虑滑带土的峰值强度和残余强度，采用不平衡推力法进行边坡稳定性分析。最终提出了与设计安全系数相对应的滑带土强度状态的分区方法和滑带土抗剪强度参数分区段取不同值的桩上设计推力的计算方法。通过对实例进行分析，结果表明本文算法得到的桩后剩余推力值与考虑残余强度的既有方法较为接近，二者的桩前剩余抗力差异较显著，本文算法得出的桩上设计推力值相对偏大。

Abstract:: In order to fully consider the difference between the peak values and between the residual shear strengths of each point on the landslide zone in the design of the anti-slide pile, aiming at the bedrock-covered landslide, this paper combines the numerical simulation with the limit equilibrium method, and obtains the stress field of the slope reinforced by anti-slide pile based on the elastic-plastic finite element analysis method. According to the relationship between the shear stress and the shear strength of a point on the landslide zone and the peak strength and residual strength of the soil in the landslide zone, the slope stability is analyzed by unbalanced thrust method. This paper put forwards the partition method of the strength state of the landslide zone soil corresponding to the design safety factor and the calculation method of the design thrust on the pile with different values of the shear strength parameters of the landslide zone soil. Through the analysis of an example, the results show that the residual thrust value after the pile obtained by calculation method in the paper is close to that by the existing method considering the residual strength, and the difference between residual resistances in front of anti-slide pile obtained by the two calculation methods is significant. The design thrust value on the pile obtained by calculation method in the paper is relatively larger than that obtained by the existing method.