巫山县老林场安置点边坡稳定性及工程治理

侯珍珠

摘要：老林场安置点边坡位于处于重庆市巫山县，巫山县城内移民安置居民点的建设形成了一系列的高边坡，给城镇居民生命财产安全带来较大的威胁。针对老林场老林场安置点边坡进行稳定性分析计算，发现边坡稳定现状为：土质（填土）边坡在各个剖面上土体整体破坏模式——天然状态下处于稳定&基本稳定但安全储备不足。饱和状态下处于极限平衡状态&不稳定状态，易在降雨作用下的解体、崩塌，并形成整体滑移破坏。岩质边坡整体处于稳定状态。结合极限平衡法及工程类比等分析手段，确定滑坡稳定性计算的物理力学参数;提出以抗滑桩加桩间挡土板为主的治理措施，对类似工程具有一定的参考价值。                                        

Abstract： The old farm resettlement site side is located in Wushan county， Chongqi province. The construction of resettlement settlements in Wushan county has formed a series of high slopes which threaten the life and property safety of urban residents. Based on the stability analysis and calculation of the slope at the resettlement point of the old forest farm， it is found that the stability of the slope is as follows： the overall failure mode of the soil mass （filled soil） slope on each section -- the soil mass is stable & basically stable in the natural state， but the safety reserve is insufficient. Under the saturated state， it is in the limit equilibrium state & unstable state， which is easy to disintegrate and collapse under the action of rainfall， and form the overall slip failure. The rock slope is in a stable state as a whole. The physical and mechanical parameters of slide stability calculation are determined by means of limit equilibrium method and engineering analogy. This paper puts forward some control measures based on anti-slide pile and soil retaining plate between piles， which is of certain reference value to similar projects.

關键词：巫山县;边坡稳定性;工程治理

Key words： Wushan county;slope stability;control project

中图分类号：U213.1+58                                文献标识码：A                                  文章编号：1006-4311（2019）20-0181-04

0  引言

老林场安置点边坡颇高，结构松散，稳定性差，易于坍滑，对老林场移民安置区威胁极大。危害对象主要为坡上移民建筑房屋面积16000m2、危害人口约500人以及移民市政道路设施。对该边坡进行工程防护迫在眉睫。

1  工程地质条件与特征

巫山县老林场处于长江三峡中的巫峡入口上游附近的长江北岸，区域地貌属于中、浅切割褶皱侵蚀、剥蚀中低山。斜坡区位于长江北岸、大宁河东岸的山地斜坡地带，属于河谷岸坡地貌。场区斜坡总体西倾，地形坡角约34°。坡顶最大高程约260m，坡脚最低高程约210m，最大高差50m。

1.1 形态特征

巫山县老林场安置点边坡原为自然边坡，后由于移民安置建设分层碾压填筑形成高边坡，现坡型由临时便道243m平台、243m平台上侧边坡以及243m平台至龙江大道内侧边坡三部分组成。临时便道243m平台长约157m，宽约45m，面积约7065m2;243m上侧边坡坡度约为27°，坡向76°，坡长约33m;243m平台至龙江大道内侧边坡坡度约22°，坡向76°坡长约65m。回填土厚度约44m，为起伏不平的回填土边坡。边坡总面积约27700m。