深基坑多层内支撑换撑拆撑方案对比分析

COMPARISON ANALYSIS OF REPLACEMENT AND REMOVAL SCHEMES FOR MULTILAYER INNER SUPPORT IN DEEP FOUNDATION PIT

现代城市建设中越来越注重地下空间的综合利用,尤其以粤港澳大湾区为代表的滨海地带,地下空间深大基坑比较常见,一般需要采用多层水平内支撑来保证基坑支护的稳定,其换撑与拆撑施工是深基坑的重要内容,也对地下室主体结构的施工安全、质量、工期等产生很大影响。以某个设置双层内支撑的基坑支护工程为实例,提出4种不同的换撑拆撑施工方案,结合考虑外墙防水、基槽回填、施工缝设置、换撑变化、施工顺序等内容进行对比分析,选择出适合项目的最优方案,以期实现最好的综合效益。

In modern urban construction,more and more attention is paid to the comprehensive utilization of underground space,especially in the coastal zone represented by the Guangdong-Hong Kong-Macao Greater Bay Area.Deep and large foundation pits in underground space are common,and multi-layer horizontal internal support is generally required to ensure the stability of foundation pit support, and the replacement and removal of support construction is an important content of deep foundation pit.Also with the basement main structure of the construction safety,quality,period of time to produce a great impact.This paper takes a foundation pit supporting project with double internal support as an example,and puts forward four different construction organization schemes.Considering external wall waterproof,foundation groove backfilling,construction joint setting,bracing change,construction sequence and so on,it makes a comparative analysis to select the optimal scheme suitable for the project,in order to achieve the best comprehensive benefits.