Mechanical Analysis And Layout Optimization Design Of Bolted Connection Structure

Due to the existence of bolt holes in the bolted connection structure,the material of the connected parts is discontinuous,which is easy to produce stress concentration and deformation,leading to the reduction of structural strength.Therefore,it is of great significance for the research of bolted connection structure to obtain the mechanical properties of the structure accurately and quickly by finite element numerical simulation analysis.For the bolted connection structure,shear is one of the main stress modes,it is necessary to analyze the various factors that affect the shear performance.Because there is often serious stress concentration phenomenon around the bolt hole,the damage of bolted connection structure mostly occurs at the bolt hole.Therefore,in order to reduce the stress concentration around the hole of the connector,make the stress distribution of the connection structure more uniform,and make the structure safer and more reliable,it is necessary to optimize the layout design of the bolted connection structure.This paper mainly carries out the following research work:(1)Based on Abaqus mechanical analysis software,the difficulties in finite element modeling of bolted structure are analyzed,and a reasonable modeling method of bolted structure is used.Finally,the parametric finite element model of bolted connection structure is established based on Python language.(2)By changing different design parameters of the structure,various factors affecting the shear performance of the single-bolted overlapped plate structure are analyzed,and the general rules of high-strength bolted shear connection are summarized.(3)In order to obtain a reasonable bolt layout design scheme,a multi-bolt connection lap plate structure is designed.Firefly algorithm is used to optimize the layout design of the structure with different bolt numbers.Compared with the initial design scheme,the stress concentration around the hole of the optimized structure is significantly decreased.(4)The finite element model of typical beam-column overhanging end plate joint is established,and the firefly algorithm is used to optimize the layout of the joint.The optimal bolt layout design is obtained,and the strength of the structure is improved to a certain extent.(5)The mechanical analysis of the holding pole and its bolt joint is carried out,and the firefly algorithm is used to optimize the layout of the bolt joint,so that the maximum circumferent stress of the joint is significantly reduced.The mechanical analysis of three different forms of multi-bolt connection lap plate,beam-column overhanging end plate and pole bolt joint is implemented.Firefly optimization algorithm is used to optimize the layout of the bolted connection structure.The maximum stress around the hole of the structure is obviously reduced and the stress concentration is obviously decreased.The optimization results indicate that the firefly algorithm in the bolted connection structure layout optimization is effective.The research results can provide reference for engineering designers in the design of bolted connection structures.