| Compared with traditional solid concrete-filled steel tube components,hollow sandwich steel tube concrete components have a better development prospect.However,the current research on this structure is mostly limited to column research,and the research on hollow nodes is relatively small,which to some extent hinders the development and application of hollow sandwich components.The node is the core part of the structure,and it is necessary to study it.Therefore,this paper designs a hollow sandwich concrete-filled steel tube column-steel beam joint with a reinforced ring plate,and uses the finite element software ABAQUS to simulate the seismic performance of the new joint.The main work,research content and conclusions of this article are as follows:（1）Using ABAQUS to establish 3 hollow sandwich concrete-filled steel tube column-steel beam test node models based on the test results,and compare the simulation results with the test results to verify the reliability and rationality of the modeling method.（2）A hollow sandwich concrete-filled steel tube column-steel beam joint model with reinforced ring slab was designed,the design method of the joint was explained,and the strength and stability of the joint design were verified.At the same time,two other hollow node models with different connection methods were established,and the three nodes were compared.The results showed that the newly designed node compared with the first two nodes in terms of hysteresis performance,carrying capacity,ductility,and energy dissipation capacity.With more improvements,it is a beam-column joint with better performance.（3）Four common cutting methods of single and combined steel beams and a new two-half-circle weakening method in steel structures are applied to the joints designed in this paper,and five joint models under different weakening methods are established and compared.Anti-seismic performance in a weakened way.（4）Establish 4 groups of 21 steel beam joint models for hollow sandwich steel tube concrete columns with reinforced ring plates on parameters such as column-reinforced ring plate diameter-length ratio,reinforced ring plate thickness,axial compression ratio,and concrete strength.Several indicators such as hysteresis curve,skeleton curve,stiffness degradation,bearing capacity and ductility,and calculated energy consumption are analyzed respectively.Discuss the change law of its mechanical properties.The results show that the performance of the new weakened joint with two semicircular webs is better than the traditional weakened joints with weakened steel beam flanges and weakened webs with circular holes.When the flange and web combination is weakened,the ductility of the joint is higher than that of the joint only when the flange is weakened or only the web is weakened,but its load-bearing capacity and energy dissipation capacity will also decrease;When the compression ratio is in the range of 0-0.6,the axial compression ratio has a greater impact on the hysteretic performance of the joint,and the increase in bearing capacity is not obvious.The ductility coefficient gradually increases in the interval（0-0.4）,（axial compression ratio 0.6-0.8）)The ductility coefficient gradually decreases;the concrete grade does not significantly affect the performance of the joint,and the bearing capacity ductility only increases slightly;when the diameter-to-length ratio is greater than 2.00,the joint hysteresis performance is not ideal;the diameter-to-length ratio varies from 3.85 to 1.56.,The bearing capacity,ductility coefficient and total energy consumption of the joint are also relatively increasing;when the thickness of the reinforced ring plate is 12mm-25 mm,the performance of the joint also increases,and the maximum stress in the core area of the joint gradually decreases.When the thickness of the joint reinforcement ring plate is insufficient（that is,when the thickness of the ring plate in this article is less than 12mm）,the seismic performance of the joint will also decrease. |
PDF Full Text Request