刘大辉，阮伟东，白 勇

(浙江大学 建筑工程学院，浙江 杭州 310058)

J-lay铺管作业力学分析

刘大辉，阮伟东，白 勇

(浙江大学 建筑工程学院，浙江 杭州 310058)

目前J-lay铺管法作为深水和超深水铺管的最适用方法广泛应用于深海油气开发。考虑J-lay铺管时管道几何非线性特征以及触地区边界效应，将J-lay铺管模型划分三构件进行力学分析：悬浮段、边界层段以及触地段。建立OrcaFlex模型和引入Wang改进二构件模型，通过对比上述三种方法计算J-lay相应构型、轴力、弯矩和剪力分布，验证该三构件模型的可行性和考虑边界效应的必要性。基于Lamé公式计算管道横截面处轴向、径向以及环向应力，对比分析J-lay铺设管道应力分布特征。结果表明：该改进三构件模型能真实有效地模拟J-lay铺管过程中管道受力情况，特别是触地点附近弯矩和剪力变化情况，能为管道疲劳损伤分析提供理论基础。

J-lay铺管；三构件模型；边界效应；弯矩失真；剪力连续

Abstract: Nowadays J-lay pipelaying method, as the most suitable pipelaying method in deepwater and ultra-deepwater, has been widely used in the deepwater oil and gas development. By taking account of pipeline geometrical nonlinearity and boundary effect in the touchdown zone during J-lay pipelaying operation, J-lay pipelaying model is divided into three segments to study: suspended segment, boundary-layer segment and touchdown segment. J-lay FEM is developed by OrcaFlex software and the developed two-fields model proposed by Wang is also introduced. By comparing the results of the J-lay configuration, tension, bending moment and shear distributions obtained from the three methods above, it can strongly demonstrate the feasibility of the proposed three-fields model and the necessity of considering the boundary effect. Based on Lamé’s equations, the axial, radial and hoop stresses on pipe cross section can be obtained and the corresponding stress distribution characteristics can also be derived. The results show that: the proposed three-fields model can realistically and effectively simulate the pipeline loading performance in J-lay pipelaying operation, especially for the variation of the bending moment and shear force near the touchdown point. It will provide a theoretical basis for pipeline fatigue damage analysis.

Keywords: J-lay pipelaying; three-fields model; boundary effect; moment distortion; shear continuity

如图1所示，J-lay铺管由于铺管过程中管线形态呈“J”型而得名[1]。J-lay铺管采用近乎垂直形态进行铺管作业，有效减小悬浮段长度，从而降低铺管船的水平动力需求，同时缩短管道触地点与铺管船距离便于动力定位[2]。目前J-lay铺管已广泛应用于深海铺管作业，特别是墨西哥湾海域。而国内外关于J-lay铺管力学研究主要包括两方面：软件模拟和理论求解。其中软件模拟主要采用Abaqus和OrcaFlex等对J-lay铺管进行静态参数分析[3]和动态响应研究[4-6]。而理论研究主要包括：Lenci等[7]针对J-lay铺管建立四种力学分析模型，指出不能忽略触地点附近边界效应，否则将会导致弯矩失真和剪力不连续。……