应用纵横弯曲梁理论分析隔水管受力变形

Analysis of Riser Mechanical Behavior Using Beam-column Theory

为了分析隔水管的受力变形,将整体隔水管视为N跨受有纵横弯曲作用的连续梁,对其中任意一跨进行受力分析并建立挠曲微分方程。根据隔水管的边界条件和各跨梁之间的连续条件求解各跨梁的解析系数,得到隔水管总体的挠曲方程。分析了不同顶张力下隔水管位移、弯矩及Mises等效应力随深水的变化规律。结果表明:建立的力学模型与分析方法将以前求解隔水管受力变形的微分方程从四阶降为二阶,降低了求解难度,为分析隔水管力学行为提供了新的方法。

In order to analyze marine riser mechanical behavior,the whole riser was modeled as a continuous beam-column with N span under actions of both axial and lateral loads.One span of the beam-column was cut out as an equilibrium unit to establish the equilibrium differential equa-tion,which can be solved on the basis of the riser boundary conditions and the continuous condi-tions between two adjacent crosses.The variation of riser lateral displacement,bending moment and Mises equivalent stress with water depth and top tension force were discussed.The results showed that the difficulty of solving riser behavior governing equation was reduced through trans-forming the four order differential equation pre-existing into a second order differential equation. The model established in this paper provided a new method to analyze riser mechanical behavior.