摘要
雨水入渗速率是影响花岗岩残积土边坡稳定性的重要因素,土体压实度作为控制土体水力特性的核心参数,其与降雨入渗过程的耦合作用机制备受关注。基于此开展了模型试验,研究了降雨条件下压实度对含孤石花岗岩残积土边坡稳定性的影响,发现:1)低压实度边坡入渗快,易发生表层冲蚀与浅层滑动;高压实度边坡入渗慢,坡顶易积水,引发局部深层裂缝和渐进式破坏。2)压实度通过控制雨水入渗速率、孔隙水压力分布和土体含水率,直接影响边坡失稳模式。3)高压实度虽能延缓边坡整体失稳,但需警惕因渗透性差导致的孔隙水压力骤增和局部抗剪强度劣化。4)孤石改变了雨水入渗路径,裂缝扩展与滑移多沿其绕流路径发展。5)低压实度边坡孔隙水压力随入渗深度增加呈阶段性波动;高压实度边坡孔隙水压力初期快速上升,后受毛细作用影响部分抵消,后期土压力因有效应力降低而显著升高。该研究为南方多雨地区边坡工程设计与灾害防控提供了重要理论和试验依据。
Rainfall infiltration rate is an important factor affecting the stability of granite residual soil slope.As the core parameter controlling the hydraulic characteristics of soil,the coupling mechanism between soil compaction degree and rainfall infiltration process has attracted attention.Based on this,the model tests were carried out to study the influence of compaction degree on the slope stability of granite residual soil with solitary stone under rainfall conditions.It was found that:1)The low compaction slope infiltrates rapidly and is prone to surface erosion and shallow sliding;The infiltration of high compaction slope is slow,and is prone to accumulating water at the top of slope,causing local deep cracks and progressive failure,2)The compaction degree directly affects the slope instability mode by controlling the rainwater infiltration rate,pore water pressure distribution and soil moisture content.3)Although high compaction can delay the overall instability of the slope,it is necessary to be vigilant against the sudden increase of pore water pressure and the deterioration of local shear strength caused by poor permeability.4)The boulder changed the rainwater infiltration path,and the crack propagation and slip developed along its flow path.5)The pore water pressure of low compaction slope fluctuated with the increase of infiltration depth;The pore water pressure of high compaction slope rose rapidly at the initial stage,and then was partially offset by the influence of capillary effect.In the later stage,the earth pressure increases significantly because of the reduction of effective stress.This study provides an important theoretical and experimental basis for slope engineering design and disaster prevention and control in rainy areas in southern China.
作者
许祥
陈勇
曾勇
李承鸿
谭静静
周全
夏楚天
侯振坤
XU Xiang;CHEN Yong;ZENG Yong;LI Chenghong;TAN Jingjing;ZHOU Quan;XIA Chutian;HOU Zhenkun(Zhuhai Liangang Urban Construction Management Co.,Ltd.,Zhuhai 519090,China;Zhuhai Hongzheng Construction Engineering Co.,Ltd.,Zhuhai 519090,China;Guangdong Hengjianyuan Engineering Co.,Ltd.,Zhuhai 519040,China;Dongqiao Investment(Zhuhai)Co.,Ltd.,Zhuhai 519175,China;School of Civil and Transportation Engineering,Guangdong University of Technology,Guangzhou 510006,China)
出处
《市政技术》
2025年第8期129-135,144,共8页
Journal of Municipal Technology
基金
国家自然科学基金项目(52208336)
广东省自然科学基金项目(2023A1515012826)
广州市科技计划项目(2024A04J3902)
广州市建筑集团有限公司科技计划项目([2023]-KJ050,[2022]-KJ002)
广州市建筑科学研究院有限公司科技进步资金项目(2023Y-KJ02)。
关键词
降雨
压实度
孤石
花岗岩残积土
边坡稳定性
rainfall
compaction degree
solitary stone
granite residual soil
slope stability
