Experimental Study on Impact Behavior of Submarine Landslides on Communication Cables

Abstract

Submarine landslides, which are characterized by large scale and long run-out, could destroy submarine tunnels, gas pipelines and communication cables, thus resulting in a great number of economic losses. Due to the harsh and extreme undersea environment, field work for landslide mechanics is nearly impossible. Therefore, a physical model test apparatus was developed in this work to simulate the motion of a submarine landslide and investigate its impact behavior acting on an underwater cable. The main part of the apparatus is an annular flume which can rotate in a vertical plane at a certain velocity. Water and soil material are placed at the bottom of the flume to simulate the submarine landslide. During the rotation of the annular flume, water and soil remain at the bottom of the apparatus under the action of gravity, and their motion relative to the apparatus bottom and cable responses similarly to a real submarine landslide. A simulant cable is set paralleling to the axel of the flume, and two load cells are fixed at both sides of the cable to measure the impact force. The relationship between the distributed load exerting on the cable with the rotation velocity and sand volume are investigated, and some promising results are obtained. Though the test results are qualitative, they still can provide a certain scientific basis for disaster evaluation of the submarine landslides and the design of underwater cables.