连续桩键结构的抗滑机制及加固效果研究

Research on anti-slide mechanism and reinforcement effects of continuous pile-plug structure

连续桩键是一种新型抗滑结构,结合了阻滑键和抗滑桩结构型式的综合功能。采用二维FLAC程序对连续桩键结构与滑坡的作用效应进行了数值模拟。分析表明,结构的内在抗滑机制主要体现于有效减小滑带区域的剪切变形量、降低塑性区的发展程度、阻滞滑坡体的整体位移、调动滑体区域的岩土体抗力等方面,而其外在抗滑机制则对应于结构能有效加固设置区域岩土体和充分发挥整体抗滑支挡这两种作用。总体上结构处于剪切、弯曲和拉压的复杂受力状态,内力变形连续分布且均衡,相当于整体协调受力的连续刚架体系,其抗滑效果更加明显,并表现出良好的工作状态。连续桩键结构克服了单体结构的应用局限问题,而更充分发挥了对滑坡体的加固阻滑效果,显著提高了滑坡体的整体稳定安全裕度,对滑坡治理工程有更广泛的适用性,已被成功应用于三峡库区最复杂的地质灾害治理项目——猴子石滑坡治理工程,取得了良好的治理效果。

Continuous pile-plug structure is a new-type anti-sliding structure, with the combination of function of shear plug and slide-resistant pile. The FLAC2D numerical modeling program is used to model the relationship between continuous pile-plug structure and landslides. The result shows that, the internal anti-sliding mechanism of the structure can decrease shear deformation, reduce plastic zones, block slide displacement, mobilize rock-soil resistance;and the external mechanism is the reinforcement effect and retain function. In general, continuous pile-plug structure works under complex stress state with bending moment, shear force and axial force, and the internal force deformation distributes continuously and balanced corresponding to continuous rigid-frame under balanced force. Continuous pile-plug structure solves the limitation of monomer structure and behaves better in slide resistance and reinforcement of landslides. It improves the safety margin of mass movement stability significantly and has wider applicability in landslides management project. The continuous pile-plug structure is applied in Houzishi landslide control engineering, which is the most complex geological hazard control project in Three George reservoir, and obtains good governance effect.