复杂环境下深水深埋承台钢板桩围堰施工技术

Steel Sheet Pile Cofferdam Construction Technology of Deep Water Buried Base Slab in Complex Environment

东江特大桥采用左侧分离加宽方式,新桥设置在旧桥左侧(上游侧)1 m外,紧邻旧高速环境下,给施工带来极大的不便;其中3#、4#墩位于东江中,水深约为12 m,承台埋置于河床以下5.5 m左右的砂砾层上。承台采用超长钢板桩围堰进行施工,封底厚度2.5 m,整个围堰施工水深最深可达20 m。相较于相似项目采用双壁钢围堰或锁扣钢管施工方案,采用钢板桩围堰施工更简单、快速、经济,对今后深水深埋结构物施工具有一段参考价值。

Dongjiang River Bridge is built by using the mode of separating and widening on the left.The new bridge is 1 m away from the left(the upstream side)of the old bridge and is adjacent to the old expressway,which causes great inconvenience to construction,as pier 3#and pier 4#are in Dongjiang River.The water is about 12 m deep.The base slab is buried in the gravel bed about the depth of 5.5 m under the riverbed.The base slab is built by the super-long steel sheet pile cofferdam.The end of the base slab is 2.5 m thick,and the overall cofferdam construction depth reaches up to 20 m.Compared with similar projects which use double-wall steel cofferdam or lock steel tube construction,the steel sheet pile cofferdam construction is easier,faster and more cost-efficient and has some reference values for the construction of deep water buried structure in the future.