导管架平台碰撞极限承载力的非线性集群并行计算

将并行计算理论和方法引入到导管架碰撞极限承载力的非线性分析中,根据美国石油学会API RP 2A-WSD标准中的方法建立桩腿非线性抗侧力-位移曲线,考虑桩-土非线性的特点分析导管架碰撞极限承载力。利用该方法对埕岛油田某导管架平台的碰撞极限承载力进行研究,分别得到平台在碰撞力作用下的平台顶部荷载-位移曲线、主桩腿弯矩变化、Mises应力变化曲线等。将集群并行运算的结果与单一PC机的结果进行对比,验证并行计算的计算精度和计算效率,同时研究不同影响因素对并行加速比和并行效率的影响。计算结果表明:平台主桩腿最大位移、应力随碰撞位置的降低而增大;碰撞位置越低,平台的碰撞极限承载能力越大;并行计算所得到的结果与单一PC机运算得到的结果相差很小,是可信的;并行加速比随着参与并行结点数的增加而增大,并行效率随着参与并行结点数的增加而下降;随着模型节点和单元数目的增多,集群的并行效率提高,并且越复杂的模型和结构在进行计算时集群并行计算能力的优势越明显。

Nonlinear analysis of collision ultimate bearing capacity with offshore jacket platform based on cluster parallel computing

By means of parallel computing, the nonlinear analysis of collision ultimate bearing capacity was studied for offshore jacket platform in Chengdao Oilfield. The nonlinear p-y curves of pile were obtained based on API RP 2A-WSD. The collision ultimate bearing capacity was analyzed considering the nonlinear characteristics of pile-soil. The displacement-load curves of platform, moment curves and Mises stress curves of main legs were obtained according to this method. The results based on parallel computing were compared with the results based on personal computer. In addition, the factors affecting parallel efficiency were also investigated. The results show that the collision ultimate bearing capacity, maximum displacement and stress of offshore platform legs decrease with the increase of impact location height. Parallel computing results can meet the actual engineering demands, and have little difference from personal computer ones. The parallel speedup ratio will increase with the increase of parallel node number, and the parallel efficiency will decrease with the increase of parallel node number. The advantages of parallel computing are more obvious when the models are more complex.