砂质海床的侧向稳定性研究.pdf

Ocean Currents-Induced Pipeline Lateral Stability on Sandy Seabed 1 2 3 4 Fu-Ping Gao ; Shuming Yan ; Bing Yang ; and Yingxiang Wu Abstract: Unlike previous mechanical actuator loading methods, in this study, a hydrodynamic loading method was employed in a flow flume for simulating ocean currents induced submarine pipeline stability on a sandy seabed. It has been observed that, in the process of pipeline losing lateral stability in currents, there usually exist three characteristic times: 1 onset of sand scour; 2 slight lateral displacement of pipeline; and 3 breakout of pipeline. An empirical linear relationship is established between the dimensionless sub- merged weight of pipeline and Froude number for describing pipeline lateral stability in currents, in which the current-pipe-soil coupling effects are reflected. Scale effects are examined with the method of “modeling of models,” and the sand particle size effects on pipeline stability are also discussed. Moreover, the pipeline stability in currents is compared with that in waves, which indicates that the pipeline laid directly upon the sandy seabed is more laterally stable in currents than in waves. DOI: 10.1061/ASCE0733-93992007133:101086 CE Database subject headings: Submarine pipelines; Ocean waves; Stability; Sea floor; Hydrodynamics. Introduction anchored or trenched, which would increase economic investment and also complicate the design and construction. In the current One of main problems encountered with the use of submarine pipe