S型铺管中上弯段管道受力研究

在使用S型铺管法铺设海底管道过程中,位于托管架上的管道(简称为上弯段)因受到较大的张力、弯矩及托管架的支撑反力作用,容易发生局部屈曲破坏。文中将托管架简化为连续型和滚轮支撑型两种,对连续型托管架上的管道进行了理论研究,并利用非线性有限元方法模拟了滚轮支撑作用下海底管道的受力状态。然后以12英寸管道为例,将两种托管架上的管道应变分布进行了对比。结果表明在连续型托管架上管道应变是一条直线;而滚轮支撑托管架上应变为波浪线,在滚轮作用处较大,滚轮之间较小。而且,应变随着张力的增大而增大,随托管架半径的增大而减小。

Mechanical study on overbend segment of submarine pipeline during S-Lay

During S-Lay operation,the pipeline on stinger which is called overbend segment,will be subjected to severe tension,bending moment and supporting reaction from stinger.The load combination could become critical and local buckling may occur in the overbend segment.The stinger is simplified as continuous and roller-supported structures in this paper.Theoretical study is carried out on mechanics of overbend segment with the assumption that the stinger is a continuous brace.Meanwhile,a nonlinear FEM program is developed for the simulation of pipeline on roller supported stinger.The distributions of strains of overbend segment on the two kinds of stingers are compared through the example of 12-inch pipe.The results show that the curve of strains is a straight line on continuous stinger and a wave line which is greater at the rollers and smaller between them on roller-supported stinger.Moreover,the strains of overbend segment increase as the tension increases or the radius of stinger decreases.