由于自升式平台二次插桩或多次插桩在同一区域形成较多形状各异的散点状桩坑，反复插拔桩区域地形起伏较大。当自升式平台二次就位时，自升式平台入泥起算深度在反复插拔桩区域计算存在较多问题，如海底起伏、桩靴差异、土体不均匀等导致常规计算方法得出的计算结果不准确。通过总结此类问题，对比现有计算方法，结合物探地形资料、拖航船实时水深，提出一种适合反复插拔桩区域的入泥起算深度确定方法，提高在反复插拔桩区域自升式平台入泥深度计算的准确性。

Due to the many scattered pile pits of different shapes formed in the same area by double or multiple pile insertion of jack-up platform， the topographic relief changes greatly in the area of repeated insertion and removal of the pile. When the jack-up platform takes its place once again， there are many misunderstandings in the calculation of the initial mud depth of the jack-up platform， resulting from the seabed relief， pile shoe difference， and nonuniformity in the soil body. We summarize several common misunderstandings， compare the existing calculation methods， combine the geophysical topographic data， the real-time water depth of the towing ship and the change of pressurized current in the control room of the jack-up platform， and propose a method for determining the initial mud depth suitable for the area of repeated pile insertion and removal. This method improves the accuracy of calculation of mud depth for jack-up platform insertion in the area of repeated pile insertion and removal.