河南某基坑失稳原因分析及应急方案  

Analysis and emergency plan for instability of a foundation pit in Henan

作　　者：张永雨 孙玉永 ZHANG Yongyu;SUN Yuyong(Henan Provincial Communications Planning&Design Institute Co.,Ltd.,Zhengzhou 451450,Henan,China;School of Civil Engineering and Architecture,Tongling University,Tongling 244000,Anhui,China)

机构地区：[1]河南省交通规划设计研究院股份有公司,河南郑州451450 [2]铜陵学院建筑工程学院,安徽铜陵244000

出　　处：《矿产勘查》2021年第5期1250-1255,共6页Mineral Exploration

基　　金：安徽省教育厅自然科学研究重点项目(KJ2019A0705)资助。

摘　　要：土层强度指标是基坑支护设计的重要参数,取值不当将影响支护设计的合理性,甚至造成工程事故。本文以某失稳基坑为工程背景,通过现场调研、土工试验、计算分析、工程经验等方法,提出地勘资料不准确、地基施工、超挖、支护不及时等是造成基坑失稳的主要原因。通过对比分析,估算出土层受施工影响后抗剪强度和承载力的折减系数,并针对性提出了应急方案,为类似基坑工程的设计和施工提供借鉴。The strength indexes of soil are important parameters for designing the foundation pit.If the strength indexes of soils are inaccurate,the rationality of retaining structures will be affected,even cause project accidents.In this paper,based on an instability accident of a foundation pit,the reasons that caused the accident have been analyzed though field investigation,geotechnical test,computational analysis and engineering practices.It found that inaccurate information of geological survey,improper construction,over-excavation and delay of supporting are the main reasons causing the accidents.By comparing analysis,the reduction coefficients of the shear strength and bearing capacity of soil layer affected by construction is estimated.Meanwhile,the emergency plan is proposed to remedy the situation,which provides reference for the design and construction of similar foundation pit.

关 键 词：基坑工程 失稳破坏 管桩施工 时空效应 折减系数 

分 类 号：TU43[建筑科学—岩土工程]