基坑工程完全可回收支护结构设计与应用

Design and application of recyclable supporting structure of deep excavation

常州汽车电子和照明研发中心项目基坑面积约17000 m 2,挖深约10 m。基坑周边邻近变配电间、河道、道路及管线等保护对象;结合基坑特点及环境特点,该项目基坑采用“整坑顺作”+“型钢水泥土搅拌墙”+“一道装配式预应力型钢组合支撑”的完全可回收支护体系方案;并通过理论计算分析与工程应用,对装配式预应力型钢组合支撑体系的受力及变形性状等进行研究、探讨。工程实施表明,该工程支护体系方案有效地控制了基坑变形,保护了周边环境,采用的可回收支护结构大大地加快了施工效率,缩短了工期,全部钢材的回收重复利用率达到了98%,取得了良好的社会经济效益,也进一步推动基坑工程的绿色、节能降耗技术发展。

The foundation pit area of the Changzhou Automotive Electronics and Lighting R&D Center project was about 17000 m 2,and the excavation depth was about 10 m.The foundation pit was adjacent tomany protection objects such as power distribution rooms,rivers,roads,and pipelines.In combination with the characteristics of the foundation pit and environmental characteristics,bottom-up method was used for the foundation pit.Steel-cement mixing wall was used as the retaining wall and fully recoverable prefabricated prestressed steel composite strut was used as horizontal support.The stress and deformation properties of the prefabricated prestressed steel composite strut were studied by theoretical analysis and engineering application.The engineering implementation has shown that the support system scheme of the project effectively controls the deformation of the foundation pit,protects the surrounding environment,and adopts a recyclable support structure that greatly accelerates construction efficiency and shortens the construction period.The recycling and reuse rate of all steel materials has reached 98%,achieving good social and economic benefits,and further promoting the development of green,energy-saving and consumption reducing technologies in the foundation pit project.