软土地基文物建筑地下空间开发的关键技术与应用

Key techniques and application of underground space development underneath heritage buildings in soft soil

城市更新中对地下空间开发利用的要求越来越高,不仅要利用既有建筑物周边的地下空间,也要深度开发其正下方的地下空间。为此,结合上海软土地基上一幢工字形文物建筑改造修缮项目,针对文物建筑正下方地下空间开发的关键技术进行介绍,包括建筑变形控制的桩基托换、与托换结构相结合的基坑支护、工字形建筑整体同步顶升和建筑隔震设计等,在项目实施过程中通过向下开挖和向上顶升的方式,经过三次结构荷载转换,实现了文物建筑正下方地下空间的开发利用。对项目实施中监测数据分析表明,文物建筑总变形和差异变形都在工程允许范围内,满足文物建筑的保护要求。

With rapidly increasing demands for urban underground space construction in the course of city renewal process,it needs not only to develop the underground space surrounding the existing building,but also to utilize the space underneath the building.An I-shaped heritage building renovation project on soft clay in Shanghai using a series of underground space development techniques,which includes settlement-controlling pile foundation underpinning,retaining and protection for excavations combined with the underpinning structure,synchronous jacking-up of the I-shaped building and the seismic isolation design,are presented.By excavating downwards and jacking-up the building upwards,during which the structural loading is transferred to the newly-constructed pile foundation in three stages,a basement has been constructed underneath the heritage building.The analysis of monitoring data during the implementation of the project shows that the total and the differential deformation of heritage buildings are both within the permissible range of the project,and satisfy the protection requirements of the heritage building.