Analysis on the Impact for Mechanical Performance of Submarine Cable During the Rock-Dumping Deburial When Repaired

Rock-dumping is a quite effective method of submarine cables protecting, but in the case of fault repair, the deburial of this dam is a challenge, requiring large flow of excavation equipment and ensuring that the cleaning process does not cause secondary damage to submarine cable. A load model was established for the cleaning process of the rock-dumping. The external load during the cleaning process was applied to the cable model, and the force on the cable under the external load was analyzed. Through numerical simulation, the dynamic cleaning process of the riprap dam model was simulated, and the stress-strain situation of the submarine cable during the cleaning process was studied. After simulation, it was found that while cleaning, maintaining a jet velocity of 30m/s, the stress on the submarine cable did not reach the yield stress, which can ensure safety; At a jet velocity of 40m/s, the yield stress can be reached within 10ms; At jet speeds of 70m/s and 100m/s, submarine cables will quickly reach yield stress and be damaged. Therefore, when using the jet method to clean the riprap dam, the jet velocity should be kept within 30m/s. At the same time, an analysis was conducted on the splashing and falling of stones caused by the jet. During this process, the maximum stress caused by the stones on the submarine cable was 0.9Mpa, which is much smaller than the yield stress, and the cable will not be damaged.