门型微型抗滑桩的前、后桩体受力不均衡系数分析

在通平高速公路K38＋560-K38＋680高边坡微型抗滑桩加固工程中，假定桩体外力为三角形分布模型，利用虚位移原理，理论推导的门型钻孔灌注微型桩前、后桩体对边坡剩余下滑推力分配比例为33：67．工后应力监测发现：桩身土压力呈近似三角形分布，前、后桩在组合桩结构中自我调整受力大小，前、后桩受力比值呈0．45-0．62-O．30规律变化，土压力向后桩转移．受荷段和嵌固段的最大剪应力都在滑面附近，前桩的最大剪力点比后桩的高一个滑床弱面夹层厚度．该工程微型抗滑桩设计的前、后桩体受力分配比对类似工程具有重要的参考意义．

The uneven coefficient analysis of gate-micro anti-sliding piles in front and back of piles under stress conditions

In the anti-sliding micro-pile reinforcement project of the K38＋560-K38＋680 high slopes for the highway from Tongcheng（Hubei province） to Pingjiang（Hunan province）, the stress of the micro-piles was assumed to be triangular distribution. The conclusion was drawn as follows, downslide thrust was distributed by the front and back piles as 33 ： 67 based on the principle of virtual displacement, the soil stress on the micro-pile was followed as the triangle distribution and in the combined pile structure, the front and back piles were adjusted by the force ratio of 0. 45 - 0. 62 - 0. 30. Mean- while, the soil stress was moved to the back pile. The maximum shear stress of the load segment and the fixed segment was found in the vicinity of the slip surface. The point with maximum shear stress of front pile was a weak interlayer thickness higher than the back pile. The allocation ratios of the front and back piles of this project can be as an ref- erence to the similar projects.