EXPERIMENTAL STUDY ON IMPACT FORCES OF SUBMARINE LANDSLIDES ON PIPE LINES

Submarine landslides frequently damage communication cables and gas pipelines on the ocean floor, resulting in economic losses and social problems. To study the impact of submarine landslide motion on a pipeline or submarine cable, a rotatory apparatus and a static apparatus were developed to simulate the interactions between the submarine landslide and cable. The static appratus was designed to simulate the relative action between soil and pile when a landslide is in the initial stage. While the rotatory apparatus was designed to simulate the relative action when the landslide moves for large displacement and has high velocity.

In the experiments with the static apparatus, the impact force of dry soil on pile line was measured when the pipe was moving through the soil. In the experiments with the rotatory apparatus, soil and water were put in the apparatus and a model cable was fixed in the rotatory part, so the relative motion of the landslide and cable can be measured and evaluated. In addition, shear stress gauges, a pore pressure transducer, and a normal stress sensor were installed at the bottom of the apparatus to monitor the stress change during the model slide motion.

In this paper, test results of landslide impact force on the cable model are presented to demonstrate the influences of landslide motion velocity and other parameters, and a comparison with other estimation methods is reviwed.