海床土体固结效应对平台拔桩吸附力的影响

Effects of Seabed Soil Consolidation Effect on Platform Pile-Pulling Adsorption Force

针对自升式钻井平台插桩完成后,随着平台作业时间的推移,插桩扰动土体固结,造成在拔桩过程中吸附力随固结时间推移而增大的现象,对准确预测平台拔桩阻力带来很大难度,根据吸附力产生机理,设计了一套试验装置。通过试验和ABAQUS研究土体固结过程中拔桩阻力与吸附力两者之间的关系,明确拔桩过程中吸附力的大小以及所占比例。研究结果表明,海床土体固结后,吸附力占到平台总拔桩阻力的以上,是平台拔桩阻力的重要组成部分,因此拔桩吸附力的科学计算对保证平台作业安全至关重要。

After completion of pile inserting of self-elevating drilling platform, pile inserting disturbs soil con- solidation with the passing of platform operating time, resulting in the increase of adsorption force with the passing of consolidation time. This causes great difficulty in precise prediction of plattbrm pile-pulling resistance. Therefore, a set of testing device was designed according to the forming mechanism of adsorption force. The relation between pile-pulling resistance and adsorption force in the process of soil consolidation was studied through the experiment and the ABAQUS. The size and proportion of the adsorption force in the process of pile-pulling was determined. The study shows that after seabed soil consolidation, the adsorption force accounts for over half of the overall platform pile-pulling resistance. It is an important part of platform pile-pulling resistance. Therefore, the scientific calcultion of pile-pulling force is of overriding importance to ensuring the safety of platform operation.