河流冲积平原饱和砂土区地下管线渗漏诱发地面塌陷机制研究  

The Mechanism of Ground Collapse Induced by Leakage of Underground Pipelines in Saturated Sandy Soil Areas of River Alluvial Plains

作　　者：李云峰[1,2] 张庆 陆远志 葛伟亚 周小平[1,2] 侯莉莉 郭纪祥 LI Yunfeng;ZHANG Qing;LU Yuanzhi;GE Weiya;ZHOU Xiaoping;HOU Lili;GUO Jixiang(China Geological Survey,Nanjing Center,Nanjing,Jiangsu 210016;Engineering Innovation Center for Urban Underground Space Exploration and Evaluation,Nanjing,Jiangsu 210016;Construction and Engineering College,Jilin University,Changchun,Jilin 130000)

机构地区：[1]中国地质调查局南京地质调查中心,江苏南京210016 [2]自然资源部城市地下空间探测评价工程技术创新中心,江苏南京210016 [3]吉林大学建设与工程学院,吉林长春130000

出　　处：《地质与勘探》2024年第1期105-112,共8页Geology and Exploration

基　　金：中国地质调查局(编号:DD20221732、DD20230116)资助。

摘　　要：河流冲积平原区是我国城市建设的主要区域,地层以松散冲洪积物为主,该地区地下管网破损带走松散地层极易形成隐蔽性很高的地下空洞,进而诱发地面塌陷,威胁人身财产和基础设施安全。以安庆市长风路地面塌陷为例,建立渗流、应力多场可控的等比实体模型箱,开展城市地面塌陷仿真实验,分析带水管线破损后地层中孔洞发育过程及孔洞周边各个方向应力变化特征,旨在揭示地面塌陷形成机制。结果表明:(1)安庆市长风路地面塌陷从孕育到塌陷,经历了小孔、竖直孔洞、塌陷坑三种形态,可将地下异常孔洞当作前兆进行预警;(2)河流冲积平原区城市地面塌陷的孕灾环境是地层的高渗透性地层和地下水位,诱发因子是管道的破损,尤其是污水排水管道破损;(3)城市地面塌陷危害大小主要受控于管道及地下水位相对埋深,且可以根据地层性质对塌陷坑的大小进行计算评估。该成果可为城市地面塌陷风险评价、防治区划等提供理论基础。River alluvial plain is the main area for urban construction in China,and is dominated by loose alluvial sediments in lithology.The damage of underground pipe networks often resulted in the loss of loose strata to form highly concealed underground cavities,which in turn induced ground collapse and threatened the safety of people and property as well as city infrastructures.Taking the ground collapse of Changfeng Road in Anqing City as an example,this work established a controllable proportional solid model box with multiple fields of seepage and stress,and conducted urban ground collapse simulation experiments.The development process of cavities after the damage of water pipelines and the stress changes in various directions around the cavities were analyzed in order to reveal the formation mechanism of ground collapse.Results indicate that:(1)Urban ground collapse progressed through three stages,from small holes,to vertical holes,and finally collapse pits,with underground abnormal holes serving as precursors for early warning.(2)The environment prone to urban ground collapse in river alluvial plain was characterized by the presence of high-permeability layers in the stratigraphy and the groundwater level.A pipeline leak,particularly a sewage pipeline leak,is the triggering factor.(3)The severity of urban ground collapse was primarily controlled by the relative depth of pipelines compared to groundwater level.The size of collapse pits can be calculated and evaluated based on stratigraphic properties.This research provides a theoretical basis for the risk assessment,prevention,and control zoning of urban ground subsidence.

关 键 词：城市地面塌陷 饱和砂土 致灾机制 冲积平原 长风路 安庆市 

分 类 号：P642.5[天文地球—工程地质学] P954[天文地球—地质矿产勘探]