近堤深水承台施工支护体系的设计与受力研究

Design and stress research of construction supporting system of deep-water cap near the embankment

针对近堤深水承台施工,提出不平衡土压力下支护体系设计思路。依托龙潭长江大桥主桥南塔承台支护结构的设计及施工,选用抗滑桩+钢板桩围堰、辅助降水的方案可以较好地解决此类基坑支护的问题。同时对承台基坑开挖过程对大堤的影响进行理论分析,并在施工中对大堤侧深层土体位移、围堰结构应力进行了监测,探讨了理论计算与实际位移产生差异的原因,确保了承台施工安全及大堤的稳定。

Aiming at the construction of deep-water caps near the embankment,the design ideas of the supporting system under unbalanced soil pressure were put forward.Relying on the design and construction of the supporting structure in the south tower cap of the Longtan Yangtze River Bridge project,the scheme of anti-slide piles+steel sheet pile cofferdams combined with auxiliary dewatering can better solve the supporting problem of this kind of foundation pit.At the same time,the influence of the foundation pit excavation process of the cap on the embankment was theoretically analyzed,the deep soil displacement and cofferdam structure stress at the side of the embankment were monitored during the construction,and the reasons for the difference displacement between the theoretical calculation and the practice were discussed,so as to ensure the construction safety of the cap and the stability of the embankment.