Damage Simulation And Analysis Of FRP Sandwich Panel

As a new type of building structures,sandwich panel has the advantages of light weight,quick installation and high construction efficiency,etc.At present fiberglass sandwich plates have been used for trimming and fitment,stair fence and guardrail structure,doors and windows.And has broad research prospects and development space in construction industry.In recent years,the application of composite materials in engineering practice has become more and more extensive.It is shown from the theoretical and experimental studies that weak interfacial adhesive layer and the associated damage failure have seriously affected the bearing capacity of the composite sandwich panel.So effective methods should be adopted to improve interlayer performance and enhance the interlayer fracture toughness.In the paper,theoretical analysis,test and numerical simulation have been carried out on the surface/core cracking,failure modes of delamination damage and crack propagation of the composite sandwich panels.In the simulation,the user subroutine written by Fortran,which describes constitutive relation and damage judgment,was introduced to Abaqus.By Abaqus/CAE,damage was simulated for further analysis of the laminate strength after damage.For the quasi-static fracture of the laminates,the universal testing machine was used to make the three-point bending test of the laminates in different angles for the delamination damage mechanism.In the paper,the damage fracture of laminates is studied by numerical simulation and experiment.The fiber breakage,matrix cracking and delamination damage of multi-angle fiber-laminated sandwich panel under three-point bending are compared.Above,the lamination scheme can be got which ensures the highest strength and smallest damage.The energy absorption and shearing force of foam sandwich in the process of fiber plate stress are analyzed.