复杂地质条件下锁扣钢管桩围堰施工技术控制

复杂地质条件及周边环境会在很大程度上约束施工进展，以南沿江城际铁路跨秦淮河特大桥70#墩深基坑施工为例，对其采用锁扣钢管围堰+型钢内支撑相结合的方法。经实践证明，该方法稳定可靠、止水性好、可恢复性好、经济性较好，为大型建筑深基坑开挖支护施工积累了一定的经验，对后续类似工程具有很好的借鉴作用。

Technical Control of Cofferdam Construction of Locking Steel Pipe Pile under Complex Geological Conditions

Complex geological conditions and surrounding environment will restrict the construction progress to a large extent. Taking the construction of deep foundation pit for 70# pier of Nanyanjiang Intercity Railway Bridge across Qinhuai River as an example, the method of locking steel pipe cofferdam + section steel internal support is adopted. The practice proves that this method is stable and reliable with the good water stopping, good recovery and good economy. Some experience is accumulated for the excavation and support construction of deep foundation pit for large-sized buildings, and some references are provided for the similar projects in the future.