邻近嘉陵江和轨道交通的超限深基坑支护设计分析

Analysis of Support Design for Ultra-limit Deep Foundation Pits Adjacent to Jialing River and Rail Transit

基于轨道交通保护的邻近长江、嘉陵江超限深基坑工程往往在地下水控制设计、变形控制设计、支护结构可靠性等方面面临着突出的技术难题。该文以重庆地区邻近轨道交通的临江超限深基坑边坡为例,探讨了设计过程中存在的问题,提出了保证超限深基坑支护安全的解决方法,基于此提出了采用具有重庆地区山地地质特点的“门字形双排桩+桩间两排高压旋喷桩止水帷幕”的联合支挡结构进行支护,最后分别通过第三方安全评估和现场监测的方法进行了安全影响评价和验证,可为类似超限深基坑支护设计提供参考。

To protect the rail transit facilities,the ultra-limit deep foundation pit engineering adjacent to Jialing River and Yangtze River is always faced with serious technical problems in groundwater control design,groundwater control design,the reliability of support structures,and so forth.Based on one case of a ultra-limit deep foundation pit engineering by the river and rail transit in Chongqing,the existing problems in the design process were laid out,and solutions to ensure the support safety of such engineering were discussed.On this basis,an integrated support structure of“gate-shaped double-row piles+water-stop curtain of two-row high-pressure jet grouting piles between piles”was proposed,with the terrain characteristics of mountainous Chongqing,and subsequently the safety impact assessment and verification were carried out by means of third-party safety assessment and on-site monitoring,which can provide reference for the same type of support design.