滑坡作用下海底管道分析模型的改进算法

针对RANDOLPH提出的用于求解滑坡对管道影响的解析方法中存在的管道弯矩不连续和在一定情况下求解位移函数存在奇异的问题，提出通过修改边界条件来改进该解析算法。在考虑管道位移边界条件的基础上，利用管道弯矩与位移函数之间的关系，将弯矩连续的性质转化为位移函数的边界条件并代入求解，以避免管道弯矩求解结果的不连续。随着新边界条件的引入，位移函数中的待定系数可直接由边界方程推导而出，避免求解位移函数时存在的奇异问题，提高方法的适用范围。经验证，利用改进的边界条件求解的结果符合管道真实的内力变化规律，也与有限元模拟结果一致。分析各参数对计算结果的影响规律，可为进一步研究滑坡对管道的影响提供参考。

Improved Method for Submarine Pipelines Analysis Model Under Landslide Impact

Aiming at the problem that RANDOLPH proposed parametric solutions for landslide impact on pipelines has discontinuous bending moment and the solution of the displacement function may singular under some conditions, a modified boundary condition is proposed to improve the analytical algorithm. Considering the displacement boundary condition of the pipeline and using the relationship between the bending moment and the displacement function, the property of continuous moment is transformed into the boundary condition of displacement function and added into the equation to avoid the discontinuity of the pipeline bending moment solution results. With the introduction of new boundary conditions, the unknown coefficients in the displacement function can be directly derived by the boundary equations and the singular problem can be avoided to increase the application scope of the method. It is proved that the results obtained using the improved boundary conditions accord with the real internal force variation of the pipeline and agree with the numerical solutions. The influence of each parameter on the calculation result is discussed which could provide reference for the further research of landslide impact on submarine pipelines.