Influence Of Scale Effect On Impact Performance Of Bridge Anti-collision Structure And Design Of Test Scheme

With the continuous development of my country’s transportation industry,ship-bridge collision and bridge collision avoidance have gradually become a research direction that people pay more and more attention to.However,the bridge floating anti-collision facility can adapt to large water level changes and has a relatively good anti-collision effect on large-tonnage ships,so it is of great significance to conduct in-depth research on its crashworthiness.However,there are few studies on the scale effect of large-scale bridge collision avoidance structure.Based on similar theory,this paper studies the influence of scale effect on the impact performance of bridge collision avoidance structure,and designs a suitable scaled-down test model on this basis.This article first studies the crashworthiness of 300-ton bridge collision avoidance facilities.Design three types of floating anti-collision facilities at the same time,and study the impact of flexible damping elements and floating anti-collision facilities sandwich structure types on their crashworthiness.The results show that the flexible damping element can effectively make the stress distribution of the anti-collision facilities more uniform,the maximum stress level has been significantly reduced,and the peak impact force transmitted by the ship to the bridge pier has been significantly reduced;The peak impact force on the bridge pier has dropped significantly,and the maximum stress level has dropped significantly.Then,based on the similarity theory,considering that the main body of the floating anti-collision facility is a thin-walled structure,and the production and processing errors of the similar model,the similarity criterion under the full similarity and the similarity criterion derived from the directional dimension are discussed separately in the impact performance of the floating anti-collision facility The application in the research is carried out separately with the finite element numerical analysis software as a tool.The results show that the finite element simulation based on the model obtained by the similarity criterion of full similarity can reflect the calculation results of the prototype well,and the maximum error is less than 15%.The model obtained by the similarity criterion derived from the directional dimension is used for the finite element simulation calculation.,The calculation result of the model and the calculation result of the prototype have a large error,but the relationship between the error and the degree of deformation of the anti-collision facility presents a certain law.Finally,based on the similarity criteria derived from the directional dimension,the finite element method was used to discuss the design method of the scaled test ship model with the ship tonnage as the design goal.Finally,the ship tonnage was used as the design goal to obtain a scaled ratio of 50,000 tons for the ship model.According to the reduction of the scale ratio,the deformation degree of the ship model anti-collision facility is smaller,and the calculation result of the peak impact force is more accurate.Among them,the deformation of the 400-ton barge hitting the anti-collision facility is less than 15%,which is derived from the model to the prototype The error of the results is also extremely small,and using this as a test ship,a scaled-down anti-collision facility model with the corresponding scale factor is designed,and the scaled-down crash test design of the crashworthiness analysis is completed.