钻井船插拔桩对临近桩靴承载力的拟静力模拟研究

Numerical simulation study on the influence of jack-up spudcan penetration and extraction on bearing capacity of an adjacent spudcan

自升式钻井船桩靴的插拔过程将会对临近井口平台的桩靴基础产生不利影响。基于PLAXIS软件,采用拟静力的数值模拟方法计算了桩靴承载力的变化规律,通过与模型试验结果的对比验证了方法可行性。结果表明:桩靴承载力折减率η随相对贯入深度H/h的增加而增大,即桩靴贯入深度越小,桩靴承载力的影响程度越小;折减率η随两桩靴的相对间距L/D的增大而减小,即桩靴插拔位置距已在位桩靴越远,对桩靴承载力的影响程度越小,相对间距L/D超过2.0时,影响可忽略不计。

The penetration and extraction process of the spudcan of jack-up drilling platform may adversely affect the spudcan of the adjacent wellhead platform.Based on PLAXIS software,a quasi-static numerical simulation method was adopted.The variation law of the bearing capacity of spudcan was calculated by the quasi-static numerical,and the feasibility of the method was verified by comparing with the model test results.The results show that:the reduction rateηof spudcan bearing capacity increases with the increase of the relative penetration depth H/h,that is,the smaller the penetration depth,the smaller the influence of spudcan bearing capacity.The reduction rateηdecreases with the increase of the relative distance L/D between two spudcans,that is,the farther the distance between the penetration and extraction spudcan,the smaller the influence on the bearing capacity of spudcan.When the relative distance L/D exceeds 2.0,the influence can be ignored.