海上建筑非粘结柔性管骨架层径向压溃数值模拟

摘要

In practical engineering, due to the manufacturing defects, the role of tensioner and other factors, there is a certain degree of initial ellipticity in the framework of the non-bonded flexible pipe.The main material of the skeleton layer is stainless steel, and the elastic-plastic nonlinear of the material may have an effect on the radial compressive strength.Meanwhile, the adjacent sliding of carcass layer surfaces will have some impact on the strength of the flexible pipe structures.However, the existing theories and methods ignore the influence of relative slip, initial ellipticity and material elastic-plastic nonlinearity characteristic on the crushing failure, which makes large errors in engineering applications.To solve these problems, based on general finite element software ANSYS, this paper sets up three kinds of contact mode for a numerical simulation to calculate radial displacement value of an 8-inch diameter skeleton layer in ideal circular state, the initial ellipticity state and material elastic-plastic nonlinear state, then compares the results with theoretical calculations to study the collapse resistance of un-bonded flexible pipe, finally draws appropriate conclusions, which can provide much certain reference for engineering applications.%在工程应用中,由于制造缺陷、张紧器作用等影响,海上建筑非粘结柔性管的骨架层存在一定的初始椭圆度;骨架层主要材质为不锈钢材,其材料弹塑非线性可能对其径向抗压能力产生影响;同时在径向压力作用下骨架层钢片间由于摩擦接触产生相对滑动,也会影响非粘结柔性管结构的径向强度.但现有理论方法忽略其相对滑动,并且不计入初始椭圆度和材料弹塑非线性对压溃失效特性的影响,因此工程应用中误差较大.针对上述缺陷,本文基于通用有限元软件ANSYS,设置三种接触方式,分别对8英寸骨架层进行数值模拟,求解数值模型在理想圆环状态、存在初始椭圆度状态和考虑材料弹塑非线性状态三种情况下的径向位移值,并与理论分析结果进行比较,以研究非粘结柔性管的抗压溃能力,得出相应结论,对工程应用具有一定的借鉴和参考意义.