付长静,李国英,赵天龙
(1. 重庆交通大学 河海学院,重庆 400074;2. 重庆交通大学 水利水运工程教育部重点实验室,重庆 400074;3. 南京水利科学研究院,江苏 南京 210029)
非线性波浪作用下埋置管道上波浪力简化计算
付长静1, 2,李国英3,赵天龙1, 2
(1. 重庆交通大学 河海学院,重庆 400074;2. 重庆交通大学 水利水运工程教育部重点实验室,重庆 400074;3. 南京水利科学研究院,江苏 南京 210029)
由于浅水区波浪的非线性影响显著,浅埋管道受非线性波浪荷载的影响大,为了保证管道长期运行的稳定性,在管道设计过程中需要充分考虑由非线性波浪引起的波浪力。考虑孔隙水和海床土的压缩性,基于Biot固结理论和一阶近似椭圆余弦波理论,利用分离变量法推导了非线性波浪作用下浅水区埋置管道周围海床的渗流压力,进而给出了埋置管道上的波浪力压力解析解,并与已有的文献结果进行比较。计算结果表明,在椭圆余弦波的作用下,海底管道周围海床内的渗流压力呈正弦分布,且管道所受的波浪力随着管径的增大而增大。
非线性波浪原理;渗流压力;波浪力;埋置管道;孔隙水压力;可渗海床土
Abstract: Due to the effect caused by the nonlinear shallow wave, the nonlinear wave load has a great influence on the pipelines buried shallowly. In order to ensure the stability of the pipeline, the force caused by nonlinear wave should be considered thoroughly during the pipe designing process. Taking pore water and compressibility of the seabed soil into consideration, and based on Biot consolidation theory and the first-order approximate elliptical cosine wave theory, the seepage force caused by nonlinear wave around buried pipelines in shallow water was derived by the way of variables separation, and the analytic solution of wave force around buried pipelines was proposed, and the solution was compared with others. The calculating results showed that the seepage force around buried pipelines assumed a Sine distribution under the effect of cnoidal waves, and the wave forces acting on the pipeline became bigger as the diameter increased.
Keywords: nonlinear wave theories; wave force; seepage force; buried pipeline; pore water pressure; porous seabed
随着海洋石油勘探开采步伐的加快,海底管道的建设成为开发海洋石油天然气不可缺少的关键工程之一。由于施工成本及施工难度等原因,管道铺设大多采用浅埋方式,浅水区的海上工程受波浪荷载的影响最大,波浪的传播会引起海床面波压力随周期变化,在海床中引起渗流压力,因此为了保证管道长期运行,在设计浅埋管道时必须充分考虑波浪荷载作用下管道所受竖向总波浪力。……