高水压力强透水性条件下桥梁深水基础施工关键因素

京沪高速铁路苏州西桥段望虞河大桥水中承台封底混凝土底面位于望虞河常水位下16．0m，河床下土质为强透水性粉砂土，承台封底混凝土承受的静水压力极大。通过对封底混凝土采用三维有限元程序计算，确定了封底混凝土的厚度；根据土质采用水力学渗流计算，决定了是否会出现管涌，并进一步确定承台开挖方法是采用围堰排水后开挖还是水下直接开挖。通过实践证实，上述分析比较准确，有效指导了施工，保证了工程顺利进行。

Key Construction Factors of Deep-water Foundations under High Water Pressure and High Permeability Conditions

The sub-sealing concrete subsurface of the underwater pile caps of Wangyu River Large Bridge,which is located in the Suzhou West Bridge Section of Beijing-Shanghai High-Speed Railway,is 16.0 meters below the normal water level of the Wangyu River.The soil under the waterbed is high-permeable silt,and the sub-sealing concrete of the pile caps is under high hydrostatic pressure.The paper conducted calculations on the sub-sealing concrete using the three-dimensional finite element program to determine the thic...