Study On The Multi-scale Low Speed Impact Of FRP Yacht Hull Structure

With the diversification of water sports,FRP Yacht quickly entered the public vision,and promoted the research of various properties of FRP Yacht structure.As most of the FRP yachts are driven in the coastal area,they are likely to be impacted by floating objects or falling objects in addition to being attacked by the sea water.Therefore,the research on the impact resistance of the FRP yachts has become an important research direction.In addition,the particularity and complexity of the FRP materials increase the difficulty of the research on the impact performance of the FRP Yacht hull structure.Other properties of FRP Yacht structure can be analyzed by reference to the research methods of steel ships,but the research on composite materials of FRP Yacht is totally different from that of steel ships,and the research on impact of FRP Yacht hull structure is less.Based on the multi-scale connection method and impact dynamics theory,this paper studies the low-speed impact performance of FRP Yacht hull structure.Based on the experience of a 75 foot Fiberglass yacht in a yacht factory,20 kinds of fiberglass steel plates with different layers and similar thickness were designed.The low-speed impact test was carried out according to ASTM-D7136 test method,and the contact force,displacement and absorption energy of various layers of fiberglass steel plates after different impact energy were collected.In the workbench software,the solid shell multi-scale test was carried out through the ACP module The feasibility of the multi-scale method to study the low-speed impact performance of FRP was verified by comparing the results of low-speed impact test and multi-scale low-speed impact simulation.The gray correlation evaluation method was used to impact the contact force,displacement and energy absorption of various FRP layers Through the overall evaluation of the performance,we can find out the fiberglass deck with better low-speed impact performance;apply the better fiberglass deck and the original deck to the overall fiberglass yacht structure to analyze their impact performance,build a multi-scale model of the overall fiberglass yacht structure and carry out low-speed impact simulation,compare the impact results,and different positions of the better deck fiberglass yacht The low-speed impact simulation is carried out to analyze the low-speed impact performance of the same FRP layer applied to different yacht structures.In this paper,the multi-scale solid shell model and the spring mass model are used to simulate the low-speed impact process of FRP accurately,and the calculation time is greatly reduced.Based on the comparison of displacement,contact force and absorbed energy,the grey correlation evaluation method is used to evaluate the impact performance of different layers,avoiding the single factor evaluation of the impact performance of FRP In this paper,the low-speed impact performance of a series of FRP layers in the yacht structure is compared and analyzed,which provides ideas for the subsequent design of the FRP Yacht layer,and has practical and reference significance for the future research on the impact performance of the FRP Yacht.