Wave-induced interaction between soil and flexible pipelines resting on the seaded

摘要

The hydrodynamic action of waves on offshore or coastal structures such as pipelines installed on the seabed induce soil-fluid-structure interactions such as local scour, seabed liquefaction or self-burial of the pipe. A large tank filled with saturated sand was built at Laboratory 3S to allow full scale modelling of the pipe response to waves. The cyclic hydrodynamic forces were simulated by horizontal and vertical actuators. The testing program was oriented first to determine the vertical penetration of the pipe according to the soil and wave conditions, and then to evaluate the lateral resistance of the soil after cyclic loading. The experimental results indicate that this lateral resistance is clearly a combination of two effects: (ⅰ) passive pressure induced by the soil in front of the pipe and (ⅱ) classical Coulomb- type friction between the soil and the pipe. The occurrence of local liquefaction of the seabed during cyclic loading was also put into evidence.