摘要
台风暴雨常引发大量的滑坡灾害,造成生命财产损失,因而研究台风暴雨条件下滑坡地下水渗流特征及成因机制对滑坡的防治、预警预报具有重要意义.以浙江省中林村滑坡为例,采用有限元数值方法,模拟了台风暴雨的两种常见工况(工况1:等强度降雨;工况2:渐变强度降雨)下滑坡地下水的暂态渗流场及稳定性.结果表明:两种工况条件下,滑坡地下水渗流特征基本相同,地下水位响应迅速,地下水位位于强风化和中风化接触面附近,且在坡脚形成溢流;但是工况1较工况2地下水水位上升速度快、幅度大;滑坡稳定系数与地下水水位及降雨强度等密切相关,在高强度降雨条件下,随地下水水位上升稳定系数快速下降,水位稳定以后,稳定系数下降速度减缓;中林村滑坡为典型的滑塌-拉裂-蠕滑缓动型变形破坏模式,台风暴雨引起斜坡岩土体地下水水位上升,基质吸力降低和孔隙水压力增加是其发生变形破坏的主要原因.本文所得结论能够为东南沿海地区台风暴雨诱发滑坡的预测预报与防治提供理论支持.
Typhoon rainstorm usually causes a large number of landslides leading to property and life losses.The research on the characteristics of groundwater seepage and genetic mechanism of landslides,therefore,is of great significance in early warning and forecasting of typhoon-induced-landslide.Taking Zhonglincun landslide located in Zhejiang province as an example,the paper used finite element method to simulate the transient seepage field and stability of the landslide under two conditions including rainfalls with constant intensity of 200 mm/d and gradually increased intensity.The results showed that the characteristics of groundwater seepage under both conditions were almost the same.The groundwater level responded rapidly and finally approached near the contact between strongly and moderately weathered strata,in addition,the ground water overflowed from the slope toe.The rising speed of groundwater level,however,was faster and the range was larger under the first condition.The factor of safety was closely related to the ground water level and rainfall intensity.Under the former condition,factor of safety decreased rapidly with increased water level,the falling speed slowed down after the water level became roughly stable.Failure mode of the Zhonglincun landslide can be summed up as creep-crack and slide-crack-creep,while rise of water table,decrease of matrix suction and increase of pore pressure in the slope were the main reasons leading to the failure of Zhonglincunlandslide.
出处
《地球科学》
EI
CAS
CSCD
北大核心
2017年第12期2354-2362,共9页
Earth Science
基金
中国地质大调查项目(Nos.1212011140010
DD20160282)
关键词
台风暴雨
滑坡
渗流
地下水
成因机制
工程地质
typhoon rainstorm
landslides
seepage
groundwater
failure mechanism
engineering geology.
作者简介
张泰丽（1980），女，高级工程师，博士研究生，主要研究方向为地质灾害调查评价．ORCID：0000-0001-5980-6496E-mail：zhangtaili@126．com;通讯作者：周爱国，ORCID：0000—0002—5491—6773．E-mail：aiguozhou@tug．edu．cn
