成层土中吸力锚极限承载力的数值模拟及分析

Numerical Simulation and Analysis of the Bearing Capacity of Suction Anchor in Layered Soils

近几十年来,吸力锚由于其灵活性和成本效益,已在海洋油气行业得到了广泛的应用.实践表明该种结构对于砂性土、黏性土和成层土等各种复杂的土质地基条件具有普遍的适应性,但是在不同地基条件下承载力差异较大,并且其最优加载点的位置也会发生改变.以成层土中吸力锚为研究对象,使用有限元数值模拟软件ABAQUS为计算工具,探究了不同土层高度和组合荷载条件下吸力锚承载力与最优加载点变化规律,并给出了V-H组合加载模式下的破坏包络线.结果表明,随着上覆土层厚度的增加,吸力锚在V-H组合加载模式下的极限承载力逐渐减小并趋于稳定,最优加载点的位置先下降再上升,之后保持不变.

Suction anchor has been widely used in the offshore oil and gas industry in recent decades due to their flexibility and cost-effectiveness.Practices show that it is generally adaptable to a variety of complex soil conditions such as sandy soils,cohesive soils and layered soils,but the bearing capacity varies significantly under different soil conditions,and the location of the optimal loading point may also change.In this paper,the finite element numerical simulation software ABAQUS is used as the calculation tool to investigate the variation of suction anchor bearing capacity and optimal loading point under different soil height and combined load conditions.The failure envelopes under V-H combined loading mode are also calculated.The results show that with the increase of the height of the soft soil layer,the ultimate bearing capacity of the suction anchor decreases gradually and tends to be stable under V-H combined loading mode,and the location of the optimal loading point descends first and then raises,and remains stable afterwards.