某特大桥深水钢板桩围堰设计探讨

针对水深超过20 m的软基河床的桥梁基础施工,科学确定了钢板桩的封底混凝土的厚度和入土深度;针对软基的河床,采用了强化内支撑受力体系的钢板桩围堰结构,并对围堰结构进行了设计计算。结论为:围堰的封底混凝土和基坑稳定均满足要求;计算得到的30 m长深水软基钢板桩围堰最大应力为137.6 MPa,最大变形为4.8 mm,均满足要求;同时模态分析表明围堰的稳定性也满足要求。钢板桩围堰施工安全顺利,并且节约了成本,保证了工期。

Discussion on Design of Steel Slab Pile Cofferdam in Deep Water

In view of bridge foundation construction in the soft soil riverbed in over 20 m-deep water,the thickness of bottom sealing concrete and depth of the steel slab pile cofferdam is defined reasonably.To the soft riverbed,steel slab pile cofferdam to reinforce internal net-surpport system is used,and the design and calculation are performed for the cofferdam.It comes to the conclusion that the stability of slab pile and bottom sealing concrete meet the request.The maximum stress of 30m steel slab pile cofferdam is 137.6 MPa,and the maximum deformation is only 4.8mm,which both meets the request.Besides,mode analysis shows the stability of the cofferdam also sufficient.In addition,the construction is conducted in a safe,economic way with the time limit for the project is ensured,which can provide reference for other similar bridge foundation construction.