装配式预应力张弦梁基坑支护系统施工技术要点探析

近年来,深基坑的开挖技术和支护系统得到高速发展和推广,目前逐步向装配式、绿色化发展。与传统混凝土支撑相比,预应力张弦梁钢支撑体系具有体系简单、安装拆卸效率高及稳定性好等优点,能有效缩短施工周期。另外,支撑体系的钢构件可以回收再利用,节约了施工成本,具有良好的经济效益。本文以厦门SM马銮湾项目基坑支护及降排水工程为例,分析预应力张弦梁钢支撑体系的施工技术参数、工艺流程及施工方法和要点。对预应力钢支撑的安装、液压式千斤顶预应力施加及支撑拆除进行了详细探讨,以期为其他同类工程提供技术参考。

The excavation technology and support system of deep foundation pit have been developed and popularized at a high speed.At present,they are gradually marching towards prefabricated and green construction.Compared with the traditional concrete support,the prestressed tension-string beam with steel support system has the advantages of simple system,high installation and removal efficiency,and good stability,which can effectively shorten the construction period.In addition,the steel components of the support system can be recycled and reused,which saves construction costs and has good economic benefits.Taking the foundation pit support and drainage works of Xiamen SM Maluanwan project as an example,this paper analyzes the construction technical parameters,process flow,construction methods and key points of the prestressed tension-string beam with steel support system.The installation of prestressed steel support,the application of prestress by hydraulic jack and the removal of support are discussed in detail,so as to provide technical reference for other similar projects.