基于水流牵引力的河道岸坡稳定性分析  

Stability of river bank slope based on water flow traction force

作　　者：郭建军[1,2] 刘凯 武臻维 曹衡[1,2] 张伟 GUO Jianjun;LIU Kai;WU Zhenwei;CAO Heng;ZHANG Wei(National Engineering Research Center for Inland Waterway Regulation,Chongqing Jiaotong University,Chongqing 400074,China;School of River and Ocean Engineering,Chongqing Jiaotong University,Chongqing 400074,China)

机构地区：[1]重庆交通大学河海学院,重庆400074 [2]重庆交通大学,国家内河航道整治工程技术研究中心,重庆400074

出　　处：《水运工程》2024年第7期226-231,238,共7页Port & Waterway Engineering

基　　金：重庆市自然科学基金项目(CSTB2022 NSCQ-MSX0991);重庆市教委科学技术研究项目(KJQN202100742)。

摘　　要：基于极限平衡理论,结合水平条分法,将Bishop法的竖直条间力关系转换到水平土条上,推导出水流牵引力作用下均质岸坡稳定安全系数的理论计算公式,将其结果与ABAQUS有限元软件的强度折减法模拟的计算结果进行对比分析。结合工程实际,分析水流牵引力对不同坡比河流岸坡的稳定性影响规律。结果表明,理论计算公式与软件模拟的结果基本吻合,误差不超过2.1%。河流中水流牵引力会增大岸坡土体的下滑力矩,降低河流岸坡土体稳定安全系数;当岸坡土体遭受降雨、坡脚土体劣化作用等多因素作用下而处于临界稳定状态时,水流牵引力可能成为滑坡启动的关键因素;在河流岸坡失稳滑动时,水流牵引力将导致滑体向河道方向滑移更远距离,加重滑坡对河流航道安全的危害;坡度越陡,岸坡稳定安全系数受水流牵引力的影响越大。在进行高陡河流岸坡稳定性分析时,水流牵引力是与强降雨、泥石流等因素同样重要且不可忽视的导致岸坡灾变失稳的外部荷载作用。Based on the limit equilibrium theory,combining with the horizontal slice method,we convert the vertical inter-slice force relationship of Bishop method to the horizontal soil strip,derive the theoretical calculation formula of the stability safety factor of homogeneous bank slope under the action of water flow traction force,and compare the results with the simulation results of ABAQUS finite element software s strength reduction method.Then we analyze the influence law of water flow traction force on the banks with different slope ratios combining with engineering practice.The results show that the calculation results of theoretical calculation formula and simulated by software are basically consistent,and the error does not exceed 2.1%.The water flow traction force of river will increase the sliding moment and reduce the stability safety factor of the river bank slope soil.When the soil is in a critical stable state under the action of multiple factors,such as rain and soil degradation at toe etc,the water flow traction force can become the key factor for landslide initiation.When the river bank slope is sliding instability,the water flow traction force will cause the sliding body to slide further towards the channel,which can increase the harm of landslide to the safety of the channel.The steeper the slope is,the greater the influence of the flow traction force on the slope stability safety factor is.In the analysis of bank slope stability of high and steep rivers,the water flow traction force is an external load that cannot be ignored,which is as important as heavy rainfall,debris flow and other factors.

关 键 词：水流牵引力 岸坡稳定性 极限平衡法 有限元强度折减法 

分 类 号：U656.3[交通运输工程—港口、海岸及近海工程] TU432[交通运输工程—船舶与海洋工程]