Simplified Calculating Study On Impact Resistance Of Tubular T-joint Strengthened By Ring Plate

With the rapid rise of the economy,the steel pipe processing and production technology has also been greatly improved.Together with the excellent mechanical properties,high quality,light weight and beautiful shape of the steel pipe,the steel structure has a large span structure,a bridge structure,and an offshore platform.Applied.Steel pipe joints are the most important components in steel structures.Their mechanical properties and ultimate bearing capacity are critical to the integrity and safety of the structure.Therefore,it is necessary to carry out research on steel pipe joints.At present,many scholars have more research results on various types of nodes under static and cyclic loads,and their research methods and contents have basically reached a mature stage.However,there are still serious deficiencies in the research on various types of nodes subjected to impact,explosion,fire,etc.There is a lack of specifications and literature on the overall performance evaluation of steel structures after catastrophic accidents,so the impact resistance of structures or nodes is developed.The research is very necessary.In this paper,finite element modeling of the T-shaped steel tube joints with ring-shaped plates is carried out by using ABAQUS finite element software,and the mechanical properties and failure modes of the joints under impact loading are studied.The research in this paper mainly includes the following aspects:(1)Model the T-node by the limited software ABAQUS to verify the validity of the model.By comparing the modeling process of the node and the simulation data of the extraction node with the impact time history curve and displacement time history curve of the test,the validity and reliability of the T-node model studied in this paper are verified.The comparison results show that the finite element simulation results agree well with the experimental results,so the accuracy of the nodes can be proved and the basis for the parameter analysis and mechanism analysis will be provided.(2)Perform parameter analysis on the node.The T-shaped circular steel pipe joints are modeled by the finite element software ABAQUS.The parameters set in this paper mainly include the diameter ratio of the branch pipe to the main pipe,the ratio of the main pipe diameter to the wall thickness ?,the main pipe span and the pipe diameter ratio ?,and the yield of the steel.The strength ?y,the wall thickness ratio ? of the branch pipe to the main pipe,the mass M of the hammer head,and the distance g between the branch pipes,and the strengthFof the pre-added axial force.By changing the parameters of the nodes,the impact resistance of the nodes,the influence law of the impact resistance ·of the nodes,and the failure mode of the nodes are revealed.(3)Based on the parameter analysis,a practical algorithm for node impact resistance is proposed.Through the extensive modeling and parameter analysis of the T-junction of the ring-shaped plate,the main parameters of the impact resistance of the node are selected,and the main control and the maximum impact force of the T-node are analyzed.Finally,the 1st Opt software is used.The derivation of the formula gives the relationship between the amount of collapse of the main pipe roof and the parameters,and the relationship between the maximum impact force and the amount of depression at the top of the pipe,and verifies the applicability.