Research On Numerical Simulation Test Of Ultra-large Bridge Super-long Pile Foundation Collided By Vessel In Marine Environment

Since most of sea-crossing bridges were located in the busy channel, the damage orcollapse issue of bridges are becoming more and more serious. The response of pier andsuperstructure of bridge in the research of ship-bridge collision was always treated as a keypoint, but less attention was paid to the damage of bridge foundation. For the pile foundationwith elevated cap in marine environment, large ships are more likely to crash the bridge bearor pile foundation to cause the bridge damage when navigable water level is low. To ensurethe operation safety of bridge pile foundation, the characteristics when large ships crash thepile foundation with elevated cap in marine environment is quite necessary to study.Combined with Langqi Minjiang River Bridge engineering, the article analyzed theprocess of super-long large diameter pile foundation collided by ship in marine environmentunder different navigable water levels and impact positions. Through numerical simulation,the article built simplified models of ship, anti-collision facilities and the pile-soil interactionmodel, and the interaction, damage and energy transform laws in the process of ship-bridgecollision were researched. The conclusion that the change of navigable stage and the distancebetween impact point and centerline of cross-bridge have significant effect on the calculationresults of ship-bridge collision is got and it is suggest that the anterior conclusion should beconsidered when design the anti-collision facilities. The maximum tensile stress pilefoundation had been cracking damaged when the ship crashed the pile foundation withoutanti-collision facilities and the safety of pile foundation with anti-collision facilities wasanalysed and evaluated which indicates the facilities has a good applicability in the LangqiMinjiang River Bridge engineering. According to the research results, the article proposed themaximum value of tensile stress of pile foundation should be treated as one of the designstandards when design the anti-collision facilities.The research results have positive instructive effects on ensuring the operation safety ofLangqi Minjiang River Bridge pile foundation, and it has certain theory and project practicalvalue.