Theoretical And Experimental Study On The Performance Of Ship Collision Prevention Interception System For Bridges

The performance study of ship collision interception system is problem of flexible multi-body system under the action of fluid structure interaction.This study is the coupling effect between the elastic-plastic dynamic characteristics of the various components,the deformation of the flexible body,and the large-scale spatial motion of the flexible multi-body system.On the other hand,this study belongs to the impact problem in the water,where the boundary effects of the water environment and the ship impact behavior interact with each other.The research focus on the protective performance of the ship collision interception system.It proposes optimization suggestions to improve the protective performance of the interception system by enhancing the collision resistance of floating foundations,optimizing anchoring methods,and the concept of linkage energy consumption.At the same time,effective simulation analysis and experimental methods for interception effects are proposed.Based on the research methods of fluid structure interception and rigid flexible interception,this article proposes a finite element analysis and experimental method for the study of the protective effect of the ship collision interception system.At the same time,specific ideas and methods for improving the protective effect of the interception system are proposed,providing reference for engineering design and research.The main work of this article is as follows:(1)The material mechanical property parameters was determined of composite materials and steel by material mechanical performance tests.And the finite element models of the interception system structure and three types of ship were established.The idea of enhancing the impact resistance of floating foundations with composite material reinforced structures has been proposed and validated.In response to the research conditions in this article,the maximum impact force of reinforced floating foundations can be reduced by 35.7%,the maximum stress at the collision position of floating foundations can be reduced by 22.84%,and the maximum stress at the ship collision position can be reduced by 19.5%.(2)The tensile and suspension tests of mooring anchor chains were conducted,and a simplified finite element simulation method was proposed.A simplified simulation method for buoyancy has been proposed to avoid the phenomenon of "distortion" in the calculation results,and to avoid the difficulties of convergence,high computational power requirements,and long calculation time caused by using traditional fluid structure coupling methods.The impact of three different anchoring methods on interception effective performance was analyzed,and suggestions for anchoring methods were proposed.For the given conditions and floating foundation form in this article,the splayed anchoring method can reduce the maximum collision force by 16.35%,and reduce the maximum force of the mooring anchor by 12.66%.The floating foundation angle is the smallest and the stability is the best of the splayed anchoring method.(3)The performance of the interception system has been verified through experimental methods.The scaling test equipment is prepared based on the principle of similarity.The research on water tank scaling experiments has been conducted,and the reliability of simulation analysis methods has been verified by 9.94% simulation error,providing a basis for conducting larger scale pool experiments and full-scale ship collision tests.(4)The basis for selecting models of mooring anchors and interception nets for different tonnage has been proposed.The article proposed the concept of enhancing the linkage effect of multiple units in the interception system by setting up interconnected energy consuming components.Through the joint participation of multiple units,the overall protection effect of the interception system is improved,and the concept of interconnected energy consumption is verified through finite element analysis by 20.31% reduction of impact force,23.58%reduction of force on nets,and 83.28% reduction of the maximum force difference between each units.The system’s protective performance was improved and the collaborative ability of multiple units was enhanced.