基于原型监测与数值分析的深挖方渠道安全评估  

Prototype monitoring and numerical analysis-based safety assessment on deeply excavated channel

作　　者：杨天凯 刘毅[1] 崔炜[1] 范哲[1] 刘玉[1] YANG Tiankai;LIU Yi;CUI Wei;FAN Zhe;LIU Yu(China Institute of Water Resources and Hydropower Research,Beijing 100038,China)

机构地区：[1]中国水利水电科学研究院

出　　处：《水利水电技术》2020年第1期172-178,共7页Water Resources and Hydropower Engineering

基　　金：国家重点研发计划项目(2018YFC0406700,2016YFC0401602);国家自然科学基金项目(51779277);中国水利水电科学研究院科研专项(SS0145C192017,SS0145B612017,SS0145B392016)

摘　　要：针对深挖方渠道安全评估的难题,选取典型深挖方断面分析监测资料反映的渠坡运行状况,并使用ABAQUS软件开展有限元反演分析,基于实测资料和数值分析来评估深挖方渠道的渗流和变形,并以此为依据对深挖方渠道进行安全评价。结果显示:渠道区域地下水位较低,不会影响边坡衬砌稳定,渠水有微弱外渗,坡面渗水很可能来自局部含水层,渠坡渗流稳定;渠坡最大侧向变形小于40 mm,位于渠坡表层,实测位移与计算至失稳的位移值相比占比不到10%,尚无深层滑动迹象,渠坡变形有较大安全储备;强度折减法计算的渠坡稳定性安全系数为1.64,满足设计要求,抗滑桩和坡面梁结构支护效果好;渠道运行状况良好。研究结果表明,采用原型监测与数值分析相结合的方式,能较好的评估深挖方渠道的实际安全状态。Aiming at the difficult problem of the safety assessment on deeply excavated channel,the operation status reflected by the analysis and monitoring data of a typical deeply excavated section is selected,and then the relevant finite element inversion analysis is made with ABAQUS,from which the seepage and deformation of the deeply excavated channel are assessed in accordance with the measured data and numerical analysis.On the basis of this,a safety assessment is made on the deeply excavated channel.The result shows that the ground water level is lower within the area of the channel,thus cannot affect the stability of the slope lining,while weak leakage of water from the channel is there and the slope leakage possibly comes from the local aquifer therein,but the seepage from the channel slope is stable.The maximum lateral deformation of the channel slope is less than 40 mm and located on the surface of the channel slope,for which the value of the measured displacement accounts for less than 10%of the value of the calculated displacement of instability,thus no deep sliding evidence is there and larger safety reserve is there for the deformation of the channel slope.The safety coefficient of slope stability calculated by strength reduction method is 1.64,which meets the design requirements;meanwhile,the supporting effects of both the anti-slide pile and beam structure of the slope surface are better,thus the operation status of the channel is satisfactory.The study result shows that the mode of combining prototype monitoring with numerical analysis can better assess the actual safety status of the deeply excavated channel.

关 键 词：深挖方渠道 原型监测 数值分析 安全评估 边坡 膨胀土 南水北调中线工程 变形 

分 类 号：TV698.1O241[水利工程—水利水电工程]