小砩桥水中承台深基坑施工技术研究

Research on Construction Technology of Deep Foundation Pit of Underwater Bearing Platform of Xiaofei bridge

针对小砩桥跨越澄潭江工程中的水中墩基坑围堰施工,采用CT锁口钢管桩围护结构形式,设计了钢管桩围护结构参数,并采用有限元验算了围护结构的强度和稳定性,计算结果表明围堰结构满足要求。考虑到CT锁口钢管桩在卵石地层中施工难的特点,提出采用旋挖桩引桩的施工方法,设计引桩施工参数,并给出了锁口钢管桩止水及漏水处理方法,为类似的围堰施工提供参考。

In the construction of the cofferdam pit for the pier foundation under the water in the project of Xiaofei bridge crossing Chengtan River,the enclosure structure form of CT locking steel pipe pile is adopted.Then the parameters of steel pipe pile retaining structure are designed,and the strength and stability of the retaining structure are checked by finite element method.The calculation results show that the cofferdam structure meets the requirements.Considering the construction difficulty of CT locking steel pipe pile in pebble stratum,the construction method of driving pile with rotary excavation pile is proposed,the construction parameters of driving pile are designed,and the water stop and water leakage treatment methods of locking steel pipe pile are given.The above research provides a reference for the similar cofferdam construction.