坡脚开挖条件下的斜坡稳定性探究
Exploration of Slope Stability Under Slope Foot Excavation Conditions
杜伟 1赵志根1
作者信息
- 1. 安徽理工大学地球与环境学院,安徽 淮南 232001
- 折叠
摘要
[目的]探究坡脚开挖对斜坡稳定性的影响,在数值模拟的基础上对斜坡隐患点进行稳定性评价.[方法]统计分析安徽省滁州市南谯区地灾隐患点孕灾特征,将其概括划分为6类不同坡度的斜坡模型,对每类模型进行梯度开挖,建立多种开挖工况,结合有限差分法和有限元强度折减法模拟计算出每种工况下的斜坡塑性区状态、坡体位移、安全系数.[结果]在30°坡度下,开挖10 m后,其安全系数降幅最大,为22.28%;在开挖进尺为4 m的工况下,坡度从15°增加到40°,其安全系数降幅最大,为60.18%;坡度对安全系数的影响大于开挖进尺.开挖到10 m时,临空面内部既正发生剪切破坏又正发生张拉破坏,其失稳概率高于坡顶.随着开挖进尺的增加,最大沉降和水平位移都逐渐发生在临空面上部.[结论]研究成果揭示了开挖过程中斜坡稳定性变化的规律,可为类似地质灾害的防治提供借鉴.
Abstract
[Purposes]To investigate the impact of excavation at the foot of a slope on slope stability,sta-bility evaluation of hidden danger points on the slope is conducted based on numerical simulation.[Methods]This paper statistically analyzed the characteristics of geological hazard potential points in Nanqiao District,Chuzhou City,Anhui Province,and divided them into six types of slope models with dif-ferent slopes.Gradient excavation was carried out for each type of model,and a variety of excavation con-ditions were established.Combined with the Finite difference method and the finite element strength re-duction method,the slope plastic zone status,slope displacement,and factor of safety under each condi-tion were simulated and calculated.[Findings]At a slope of 30°,the factor of safety decreases by 22.28%after 10m excavation;When the excavation footage is 4m,the slope increases from 15° to 40°,and its factor of safety decreases by 60.18%,the largest proportion;The influence of slope on factor of safety is greater than that of excavation footage.When the excavation reaches 10m,both shear failure and tensile failure are occurring inside the free face,with a higher probability of instability than at the top of the slope.As the excavation footage increases,the maximum settlement and horizontal displacement gradually occur in the upper part of the free face.[Conclusions]The research results reveal the law of slope stability changes during excavation,which provides reference for the prevention and control of simi-lar geological disasters.
关键词
FLAC3D/稳定性分析/安全系数/地质灾害/切坡建房Key words
FLAC3D/stability analysis/factor of safety/geological hazards/building houses by cutting slopes引用本文复制引用
基金项目
安徽省滁州市南谯区1∶50000地质灾害风险调查项目(CZCG202109-101)
出版年
2024
NETL
NSTL
万方数据