Study On Dynamic Response Of Inland Ship-pier Collision And Anti Collision Device

With the steady growth of traffic and transportation investment in highway and railway construction,the number of bridges across inland rivers is increasing year by year.At the same time,the traffic volume of inland waterways is also increasing.These two reasons lead to an inevitably increase in the probability of collision accidents between the inland river ships and the bridge piers.The bridge collision accidents endanger the structural safety of the bridge and the safety of the ship operation.Bridge anti-collision design is a safety project that must be solved in engineering design and construction.The existing analysis theories and design specifications still have deficiencies in the research of ship-bridge collision response analysis,collision force model,anti-collision technology and other essential basic projects.On the basis of the existing research results,the finite element numerical analysis method is used to simulate the complex dynamic response of the inland river ship-pier oblique collision,and an anti-collision device with simple structure and convenient maintenance is proposed based on the results of numerical analysis.Firstly,based on the actual engineering parameters,the full size finite element model of the gravity bridge pier,the column pier and the 900 DWT inland bulk carrier are established.Meanwhile,in order to analyze the influence of soil on the pier structure,a pile-soil coupling finite element model for both gravity pier-ship collision and column pier-ship collision with are established.Then the necessity of considering the influence of soil is demonstrated by numerical simulation.The accuracy of pile soil coupling model is higher than that of pile foundation.The simulation result also shows that,the accuracy of pile-soil coupling model is higher than that of pile embedded model.Secondly,considering the action of dynamic water pressure,the finite element simulation of the collision process of gravity pier,column pier and 900 DWT bulk carrier under four collision angles and five kinds of collision speeds is carried out respectively.The time-history curve of dynamic response shows that,with the decrease of collision angle,the duration of collision process is obviously shortened and the mean of collision force increases obviously.The collision angle has little effect on the maximum peak value of the collision force.With the increase of the collision speed,the duration of the collision process is obviously increasing,the maximum peak and the mean of the collision force will increase correspondingly,and the peak of the collision force peak appears earlier.Thirdly,considering the specific navigation environment,a new type of rotatable anti-collision tube with honeycomb-structure energy absorbing box suitable for highway bridge column pier is put forward.The time-history curve of impact force,deformation energy and the deformation of ship shows that,the rotatable anti-collision tube has excellent energy absorption characteristics.With the anti-collision tube,the collision force can be reduced by about seventy percent,both pier and ship structures can be protected from the destructive effect caused by the ship-pier collision.