Parametric Simulation And Experimental Analysis Of Composite Connectors

Composite materials have good mechanical properties,and as the manufacturing process becomes more and more mature,the scope of use has expanded from the initial application of spacecraft to aviation,ships,automobiles and other directions.In these fields,it is mainly applied to largesize structural parts,such as aircraft wings,skins,ship superstructures,automobile bodies,etc.This involves the connection between composite structural parts.According to statistics,there are millions of connections on the Boeing 747 aircraft,and the number of bolt holes on the wing of the American fighter F-22 is more than 10,000.At present,there are three types of connection forms for composite materials,cementing,bolting and hybrid connection.Bolted connection has good load-bearing capacity and facilitates disassembly,so it is widely used.According to domestic and foreign literature investigations,most of the current research on composite bolt connections focuses on the numerical simulation and experimental research of single-row bolts or singlerow bolts.The main research content of this paper is the parametric simulation and test of multi-row and multi-column bolts.First,use ABAQUS for finite element simulation,use Python language to write script files,and then run the simulation model through the ABAQUS script interface,and select the strainbased three-dimensional Hashin criterion as For the damage and failure criteria for the simulation of the connector,the appropriate iteration parameters are obtained through simulation and debugging.In addition,the damage file is called through the script file,and then an independent simulation plug-in is set according to the RSG window of ABAQUS.Because the composite material multi-bolt connection structure parameters include geometric parameters,material parameters,ply parameters,etc.,the simulation calculation through plug-ins can greatly improve the simulation efficiency.Then the influence of some parameters on the connection structure is studied through experiments.The test pieces are divided into two parts: test pieces and standard pieces.The material parameters of the simulation calculation are obtained through the standard parts.The experimental parts can also be divided into two groups.One group is a multi-bolt connection structure with equal width and different row spacing,and the other group is a multi-bolt connection structure with different ply angles.Change the failure mode of these two sets of parameters,the attenuation of stiffness and damage and destruction,etc.Finally,the experimental results and numerical simulations are compared and analyzed to verify the validity of the simulation results.Finally,on the basis of the contents of the first two chapters,a parameterized simulation calculation is carried out.A script file is written through Python to control the change of single parameter or double parameter for numerical simulation calculation.The geometric parameters,ply parameters,etc.are studied for the composite multi-bolt connection structure.The influence of mechanical properties is analyzed in detail,and the transition process of the failure mode of the connector is analyzed in detail.