间歇性降雨作用下牵引式滑坡的时空演化分析和失稳判据研究  

Method for spatiotemporal evolution analysis and the instability criterion of traction landslides under intermittent rainfall

作　　者：侯小强 周重任 吴红刚 胡天翔 侯云龙 HOU Xiaoqiang;ZHOU Zhongren;WU Honggang;HU Tianxiang;HOU Yunlong(School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;Northwest Research Institute Co.,Ltd of C.R.E.C,Lanzhou 730000,China;HuaBang Xinerda Technology Corporation,Lanzhou 730026,China;Gansu Institute of Engineering Geology,Lanzhou 730000,China)

机构地区：[1]兰州交通大学土木工程学院,兰州730070 [2]中铁西北科学研究院有限公司,兰州730000 [3]华邦信尔达科技检测有限公司,兰州730026 [4]甘肃工程地质研究院,兰州730000

出　　处：《清华大学学报（自然科学版）》2024年第8期1347-1356,共10页Journal of Tsinghua University(Science and Technology)

基　　金：中央引导地方科技发展基金项目(22ZY1QA005);交通运输部科技示范工程(2024-007);甘肃省重点研发计划工业类项目(23YFGA0028);中国中铁股份有限公司科技研究开发计划(2022-重大专项-07);甘肃省交通运输科研基金项目(2022-28)。

摘　　要：目前,仅以整体安全系数难以准确量化并预测间歇性降雨作用下牵引式滑坡的时空演化过程。针对这一问题,该文提出了点安全系数时程分析方法,利用Python语言二次开发并建立了点安全系数时程计算模型,通过分析整体安全系数、点安全系数、变形位移揭示了间歇性降雨作用下牵引式滑坡的时程演化规律,并结合工程实例验证了模型的合理性。结果表明:1)利用点安全系数的时程计算结果可描述滑动面由坡脚至坡顶逐渐贯通的演化特征,为滑坡牵引段、主滑段和拉裂段的划分提供了充分的理论依据;2)点安全系数和位移相结合可作为牵引式滑坡“启动—变形—失稳”演化过程的评判依据,而整体安全系数不能单独作为评判依据;3)可依据滑坡牵引段、主滑段和拉裂段3部分的位移变化和点安全系数的大小,共同判定滑坡所处的稳定状态(稳定、基本稳定、欠稳定或不稳定),由此形成牵引式滑坡各阶段稳定状态的判定准则,且具备可靠性。该文成果可为中国间歇性降雨滑坡的预警研究提供理论依据和工程指导。[Objective]Numerous scholars,domestically and internationally,have extensively researched the initiation and occurrence of landslides under intermittent rainfall.These studies have revealed the intrinsic relationship between rainfall intensity and landslide stability.This relationship indicates that landslide destabilization and failure involve the gradual spread of the plastic zone at the sliding surface until it penetrates through.The stability of these landslides was quantitatively evaluated using the overall safety factor.To improve the accuracy of landslide prediction and forecasting,the temporal and spatial relationships between landslide evolution characteristics and stability must be deeply investigated.By combining existing monitoring technology,revealing the temporal and spatial patterns of the overall safety coefficient of landslides,point safety coefficients,displacements,and other parameters,and proposing the criteria for the stability of landslides at each stage,we can provide reliable theories and methods for the accurate early warning and forecasting of landslides.[Methods]Using ABAQUS software,a finite element model for a traction landslide was established,considering the relationship between the spatial stress and time of the slope body under intermittent precipitation.Python was implemented for the secondary development of a time-history method for analyzing point safety factors.This method allowed us to calculate the spatial point safety coefficient cloud map of the different regions of a landslide section at any time and analyze the entire process of the initiation-deformation-failure of a traction landslide under intermittent rainfall.[Results]The study yielded the following results:1)Point safety coefficient time-range calculations visually described the evolution characteristics of the traction landslide sliding surface under intermittent rainfall,gradually moving from the foot to the top of the slope.The time-history varying characteristics of the three-point safety coefficient reflect th

关 键 词：间歇性降雨 时空演化 点安全系数 稳定性分析 失稳判据 

分 类 号：TU42[建筑科学—岩土工程]