Study On The Internal Structure And Energy Dissipation Mechanism Of New Type Of The GFRP Flexible Ship Collision Protection Floating Box

In our country,in recent years,along with the progress of society,the development of science and technology and the massive investment in highway and bridge,the development of bridge industry has also been growing rapidly.However,due to the increasing number of water shipping industry in China,the bridge piers have been an obstacle to the navigation of ships,the incidence of collision accidents has been constantly improved.Many designers use passive anti-collision facilities(buffers)to protect the pier for Bridges that have been built.In recent years,the main research of the anti-collision floating box made of the new material GFRP has been applied to the absorption of ship impact force,and has obtained very good results.In this paper,it is based on the GFRP flexible anti-collision floating box project of a bridge pier,mainly studying the internal structure and energy dissipation mechanism of the new GFRP flexible anti-collision floating box through numerical simulation analysis and comparison of finite element software.In this paper,it has researched progress of ship-pier collisions,and performed a series of studies for specifications of bridge pier impact forces at home and abroad.Take design and research on the structural model of GFRP anti-collision floating box through analyzing predecessors' ideas for pontoon design.Firstly,take a series of design studies on internal energy-dissipation tube with different shapes and thicknesses in floating box,then determine the best shape and thicknesses energy-dissipation tube which absorbs the ship's best impact force.Second,contrast design the connection of the internal energy-dissipation tube on the basis of the best form of the energy-dissipation tube and determine the best connection.Finally,designing pontoons which combine with the same energy-dissipation tube and different thickness external box,determine the best combined GFRP anti-collision floating box.All of the above design simulated models are using finite element nonlinear dynamic analysis software ANSYS/LS-DYNA,and finally compared with the results from numerical simulation.At first,take understand the change of impact force and energy from the bridge piers,and select the better GFRP flexible anti-collision floating box through visually comparing their performances.Then,it compares and analyzes the energy change of the GFRP anti-collision floating boxes and observes their energy-dissipation of the these boxes.Finally,it takes a series of analysis for energy-dissipation mechanism performed of each working collision floating box,and selects the best energy dissipation effect.Analyze the energy dissipation effect and draw the following conclusions: the energy dissipation effect of 5mm thickness octagonal energy-dissipation tube is better than that of other thickness and shapes.Through directly adding the connection to the definitive form of the energy-dissipation tube,it can increase structural integrity but weaken the effect of energy dissipation.The best effect of energy dissipation of the GFRP anti-collision floating box is the combination of 5mm octagonal energy-dissipation tube with surface contact and the external box with the thickinss range of 15mm-20 mm.The research sesults will provide a reliable theoretical basis for the future design of GFRP flexible anti-collision floating box.