降雨条件下刺槐林边坡稳定性分析  

Analysis on stability of Robinia pseudoacacia forest slopes during rainfall

作　　者：陈丽华[1] 刘秀萍[1] 宋维峰[2] 高振林[3] 张超波[1] 

机构地区：[1]水土保持与荒漠化防治教育部重点实验室北京林业大学水土保持学院 [2]西南林学院环境科学与工程系 [3]北方工业大学建筑工程学院

出　　处：《北京林业大学学报》2008年第S2期211-214,共4页Journal of Beijing Forestry University

基　　金：国家自然科学基金项目(30571531);“973”国家重大基础研究项目(2002CB111502)

摘　　要：基于野外调查和室内试验分析,该文运用非线性有限元法分析了降雨条件下刺槐林边坡的应力应变情况。结果表明:降雨使得土壤含水量增加,基质吸力减小,边坡的抗剪强度降低,使原本稳定的边坡可能发生边坡失稳;土壤含水量增加,边坡坡角处向坡体内的水平位移集中带范围明显增加,边坡顶部的应力水平变化梯度增加,容易在应力水平变化梯度较大的地方形成滑落面,造成滑坡;林木根系将边坡的应力向土层深部传递,弱化根系层应力,减小土体的应力集中;根系吸收坡体内的水分,使得坡体内非饱和区域含水量增加缓慢,对边坡稳定性有利。Based on field investigation and indoor lab tests,numerical simulations were made using the nonlinear finite element method to analyze the stress change of Robinia pseudoacacia forest slopes under rainfall situation.Results indicate that rainfall makes water content of soil increase,matrix suction ability decrease,anti-shearing strength of the slope reduce,thus original stable slope may lose stability.The range of concentration zone of displacement in the area which strecteches inward from toe of the slope obviously increases,and the varying gradient of stress level on top of the slope also increases,the place where has big varying gradient of stress level could form slipping plane and lead to landslide.Forest root system can transfer the stress of superficial soil to the deep,weaken the stress of root system layer,reduce the concentration of stress in soil.Forest root system can also absorb water in the slope,make water content of unsaturated zone in the slope increase slowly,and improve the slope stability.

关 键 词：刺槐 土壤含水量 有限元法 边坡 稳定性 

分 类 号：S714.7[农业科学—林学]