深基坑支护结构开裂变形险情原因分析及应对措施  

Cause Analysis and Countermeasures of Cracking and Deformation of Deep Foundation Pit Support Structure

作　　者：吴隽 WU Juan(Shanghai Construction No.5(Group)Co.,Ltd.,Shanghai 200063,China)

机构地区：[1]上海建工五建集团有限公司,上海200063

出　　处：《建筑施工》2022年第2期248-252,共5页Building Construction

摘　　要：某深基坑施工过程中,坑外地表沉降、坑外地下水位下降、支护桩顶部竖向及水平位移、土体及支护桩深层水平位移等均出现超报警值和控制值的险情。与此同时,基坑支撑梁、冠梁和支护桩也严重开裂。现场采取坑外注浆、坑底加反压土、基坑分块开挖施工、加斜抛撑等措施,有效遏制了基坑进一步失稳的趋势,避免出现安全事故。以此为例,对基坑出现险情的原因进行分析,并从勘察、设计、施工、监测、应急响应等方面,探讨如何进行基坑安全管控。During the construction of a deep foundation pit,the surface settlement outside the pit,the drop of groundwater level outside the pit,the vertical and horizontal displacement at the top of the support pile,the deep horizontal displacement of soil and support pile all exceed the alarm value and control value.At the same time,the foundation pit support beam,top beam and support pile are also seriously cracked.The measures such as grouting outside the pit,adding back pressure soil at the bottom of the pit,block excavation of the foundation pit and adding inclined throwing support are taken to effectively stop the trend of further instability of the foundation pit and avoid safety accidents.Taking this as an example,the causes of dangerous situations in the foundation pit are analyzed,and it is discussed how to carry out the safety control of the foundation pit from the aspects of survey,design,construction,monitoring and emergency response.

关 键 词：深基坑 支护结构开裂 基坑变形 水位下降 应急抢险 

分 类 号：TU753[建筑科学—建筑技术科学]