通过动力荷载分析,确定海冰荷载可以引起平台筒边土体液化,并阐述了判别土体液化的方法。利用冰激振动软件以及有限元软件对结构进行动力学分析,得到各筒边土体的最大剪应力。通过室内三轴实验和现场观测结果确定士体物理力学参数,利用判定公式计算得到土体抗液化极限应力。将两者进行对比,可判断筒边土体是否可能发生液化。以渤海某油田筒型基础平台为例,对平台基础土液化安全性进行了判别,证明该方法具有较强的创新性和可行性,对于这一类浅基础平台的地基土液化分析有一定的实践指导作用。
It shows, by analyzing all the dynamical loads, that the ice force could cause the liquefaction of the soil around the bucket of the platform. The paper presents the method to evaluate the liquefaction potential. First, the main shear stress of the soil around the bucket was acquired by using the finite element program about soil-structure interaction. Second, by the identifiable formula based on indoor triaxial compression test and field survey , a calculation on the limited shear strength to the liquefaction was performed. By Comparing the two results obtained above,one can evaluate the liquefaction of the soil around the bucket of the platform .As an example, the liquefaction potential of offshore platform with bucket foundation in one oilfield of the Bohal Sea was evaluated, which proved that the theory and the method in this paper are innovative and feasible for such kind of platforms.