Seismic Behavior Analysis For Steel Frame Ductility Nodes With The Reinfored Plate Connected By High-strength Bolts

Up to now, the joints research based on the theory of relocation of plastic hingehave achieved some success, but all the components of the new enhanced ductilitynodes are welded together. Therefore, the welding temperature field and welding stresshas a certain influence on it.In this paper, four forms enhanced ductility nodes havebeen designed and simulated,and the enhanced plates are welded to the flange of beamand column,included the symmetrical rib plate enhanced node (SBR), the asymmetricrib plate reinforced node with “L”plate in the top flange(ABR-L), the asymmetric ribplate reinforced node(ABR) and the symmetrical “L”plate enhanced node (SBL).Usingthe finite element simulation results analyze the hysteretic performance and damagedegradation performance of the reinforced nodes with the reinforced plate connected byhigh-strength bolts.In order to analyze the enflunce for the connection form of thereifoced plate, welding reinforced nodes were compared with the nodes whosereinforced plate connected by high-strength bolts. The main content includes:1. According to the current specification in China,four kinds of reinforced nodeswhose reinforced plate connected by high-strength bolts were designed,referring AISCDesign Guide12.2.The finite element model of reinforced nodes whose reinforced plate connectedby high-strength bolts and welded reinforced reinforced nodes is established.And cyclicdisplacement load were applied on the finite element model using finite elementsoftware ansys. According to the result, the stress development, failure pattern andhysteretic performance of the reinforced nodes is analyzed whose reinforced plateconnected by high-strength bolts.And compared it with welding reinforced nodes.Analysis results show that unless the asymmetric rib plate reinforced node(ABR),plastic hinge all appear at the end of the reinforcing plate to protect the beams butt weld,full hysteretic curve, and have good ductility and energy dissipation capacity.The plastichinge of the ABR node appers near the beam flange butt weld, and the seismicperformance of ABR nod is poor. Compared with welding reinforced node, thereinforced nodes whose reinforced plate connected by high-strength bolts have a larger hysteresis loop and higher ultimate bearing capacity, and the ductility and energydissipation performance of the nodes are also better than welding reinforced nodes.3.In order to analyze the damage degradation performance of the foure reinforcednodes whose reinforced plate connected by high-strength bolts, extract the stress andcracking index distribution in the critical path and the degradation coefficient. Andcompared it with welding reinforced nodes. The results showed that the stress andcracking index in weld of the beam are slower, and the degradation are slower. Overall,SBR、ABR-L and SBR have better seismic performance,and the seismic performance ofABR node is slightly better than the ordinary node. Compared with welding reinforcednode, the nodes whose reinforced plate connected by high-strength bolts reduce thestress and cracking index in the end of reinforcing plate seriously, the degradation speedalso been reduced.On the whole, the nodes whose reinforced plate connected byhigh-strength bolts have better seismic performance.4.Summing the hysteretic behavior and degradation performance of the theenhanced nodes,the SBR connection and ABR-L connection had good seismicperformance,and the seismic performance of ABR were slightly better than the ordinarynodes.