Strength Characteristics And Load-bearing Capacity Analysis Of Typical Joint Structures Of FRP Sandwich Panels

Compared with traditional materials,composite materials have excellent mechanical properties performance.The application of composite materials to ships can reduce the weight of the ship structure,improve the stability and speed of the ship,and also Important functions such as sound insulation and stealth.The mechanical properties of composite materials are related to the number of layers,the angle of the layers,etc,and the manufacturing process is relatively complicated.At the same time,the ship structure also involves the connection with the steel members.The stress at the connection is caused by factors such as openings and sudden geometric shapes.It is too high and may eventually cause the strength of the composite material to fail.Therefore,studying the strength of the connection structure between composite materials and steel components has important engineering significance.First,the ABAQUS finite element analysis software is used to establish a three-dimensional finite element model of the bolted connection structure of the glass fiber reinforced plastic composite sandwich panel.Considering the two types of typical loads of bending and stretching,the stress distribution characteristics of the sandwich panel connection area are studied and obtained The influence of parameters such as pre-tightening force,friction coefficient between connecting members,screw hole matching method,and laying angle on the structural stress in the bolt connection area of FRP composite sandwich panels.Then,based on the Shokrieh-Hashin criterion and related progressive failure theory,a subprogram for progressive failure analysis of composite materials was developed.The program was used to simulate the failure process of the structure in the bolted area of the glass fiber reinforced plastic composite sandwich panel,and the tensile load was studied.The ultimate load failure mode of the lower connection structure reveals the influence of the pre-tightening force,the matching method,the ply angle and other parameters on the connection structure’s bearing capacity and failure mode.Finally,for a fiberglass composite sandwich panel dovetail groove type connection structure,the stress distribution characteristics and damage failure of the connection area structure are analyzed under both tension and bending conditions,and the core layer material of the connection area is studied,Dovetail tenon material,dovetail groove geometry and other parameters affect its failure mode and ultimate bearing capacity,and the corresponding laws have been obtained.The work of this paper provides a reference for the engineering design and application of the connection structure of FRP sandwich panels.