Numerical Simulation Of Ship Collision With Kilometer-scale Cable Stayed Bridge And Bridge Pier Anti-collision Equipment

Nowadays,researchers are always use numerical analysis method to study ship-bridge collision problem.This paper simulated the whole ship-bridge collision with LS-DYNA finite element software,regarding the kilometer-scale stayed bridge is located in Anhui province as back ground.According to the simulation results,such as the max collision force,dynamic response and other useful data,provides reference for the bridge design.Finally,the paper designed a floating anti-collision equipment for the bridge,and the performance evaluation of floating anti-collision equipment was performed for simulation analysis.All the works and the conclusions are as follows:(1)The basis theory of ship-bridge collision and empirical or code calculation formulas of collision force all around the world was simply introduced.Several key technologies involved in the simulation process are discussed in detail.(2)The whole ship-bridge and floating anti-collision equipment finite element model were set up.The numerical simulation on collision of concrete are carried out with HJC dynamic constitutive model,and the pile-soil interaction was also considered.(3)The changes of impact velocity,collision angle,water level and shape and dimension of bridge pier were investigated in this paper.Impact force,energy transform,bridge’s dynamic response caused by different impact conditions were analyzed and the conclusions were drew as follows: With the increase of impact velocity,the max collision force and the duration of collision increase.Except direct impact position,the part between the pile cap and pile column is the most dangerous;The ship collided with the bridge head-on and obliquely had different properties,When the ship frontally impact the bridge pier,the max collision force,the duration of collision and bridge tower top transverse displacement are maximum;different collision water level lead to different contact area and position,with the increase of the contact area,the max collision force increase,the duration of collision decrease,and the max collision force of ship pile-cap collision is larger than that of ship thin-wall bridge pier collision,but the bridge tower top transverse displacement is smaller;Compared with the rectangular pile cap,the columniform pile cap reduces the value of max collision force and in-creases the duration of collision.(4)Based on the max collision force,duration of collision,energy transform and dynamic response,crashworthiness of the anti-collision equipment was evaluated,the anti-collision equipment can decrease the impact force,prolong the contact time of ship-bridge collision and dissipate the kinetic energy of collision ship,therefore the bridge can be protected.