Ship-bridge Collision Simulation And Research On Performance Of New Type Bridge Pier Protection Device

With the development of economy,the construction of cross-sea bridges in China has entered a new stage.The number and scale of cross-sea bridges are constantly expanding,which leads to the increasing risk of ship-to-bridge collisions.Compared with the piers of the navigable hole area,the anti-collision design value of the piers in the non-navigable hole area is lower,and the ability to resist ship impact is poor.The damage of the piers will affect the safety of bridge deck traffic seriously,and even cause casualties.In this paper,a ship collision simulation is carried out on non-navigable pier of a cross-sea bridge.A new anti-collision device is proposed to analyze the protection effect of the new anti-collision device on the bridge pier.The main research contents are as follows:(1)Taking the non-navigable hole pier of a sea-spanning bridge as the research object,combining engineering design data and comprehensively considering the influence of hydrodynamic pressure and pile-soil effect,a refined ship-bridge model was established by using finite element software.The collision simulation between ship and rigid wall is carried out,and the rationality and accuracy of ship model are verified.(2)Considering the impact of ship mass,ship initial velocity,ship impact Angle and ship impact position,the ship and pier collision simulation was carried out to obtain the response law of ship and bridge under different factors,and was compared with the impact force specified in China’s regulations to verify the accuracy and reliability of the numerical model.(3)The airbag anti-collision device is put forward to protect the bridge pier,and simulation calculation of ship impact is carried out.Under the protection of airbag anti-collision device,the impact force,energy consumption and displacement of the bridge pier are greatly reduced,which verifies the effectiveness of airbag anti-collision device to protect the bridge pier.On the basis of numerical simulation of airbag anti-collision device,the factors affecting airbag anti-collision ability are studied.The results show that the initial volume of the airbag,the outsourcing material of the airbag and the initial internal pressure of the airbag all have certain influence on the protective effect of the airbag anti-collision device,so the airbag anti-collision device should be designed according to different engineering conditions in the actual project.The simulation results of the airbag anti-collision device are compared with those of the FRP anti-collision case.The results show that compared with the FRP casing,the airbag anti-collision device has a 7.9% reduction rate of impact force,and can reduce the response of the pier,which can protect the pier and the ship more effectively.