Experimental Study On The Seismic Behavior Of The Frame Joints Of A New Type Of Dry Connection Assembled Hybrid Structure

The new type of dry connection assembled hybrid structure frame node is in the reinforced concrete column and concrete beam node core particle to set a dog bone steel beam and set up a constraint on the flange and web,draw lessons from the structure of the dog bone type node in the steel structure way up and weaken on the beam end near the joint core h-beam flange for the circular arc,the plastic hinge was kept away from the root of the beam end.The beams and columns were prefabricated in the factory,and when the concrete reached the preset strength,it was transported to the site for lifting and splicing,and the prestressed steel strand is tensioned.The steel beams and concrete beams were connected with high-strength bolts through their respective connecting plates to form the mixed beam,and the beam-column joints are connected by the overhanging end plate and the prestressed tension screw and steel strand of the square steel application,the new hybrid node is convenient for on-site construction.For the realization of the on-site assembly of "building blocks",the main beam and column components are manufactured in factory batch prefabrication and assembled quickly on site to meet the requirements of normal use.this paper completed the two anti-buckling dog bone beam mid-side node,two anti-buckling dog bone beam middle nodes and one end plate energy dissipation type middle node under low reversed cyclic loading.The experiment focuses on the effect of prestress size on the seismic performance of the side and middle nodes,and the seismic behavior of the joints in the end plate dissipative frame was also analyzed.Through the observation of the experimental phenomena of each specimen and the processing of the experimental data,the side and middle joints were analyzed from the aspects of failure pattern,crack development and seismic performance of the specimen.The results show that after the prestress was applied to the side and middle nodes of the anti-buckling dog-bone steel beam,the bearing capacity of the specimens increases,the limit displacement increases,the stiffness degradation slows down,the energy consumption increases,and the hysteresis curve becomes more full.After the prestress was applied,the time of cracks on the concrete beam was delayed and the number was reduced.In the end plate energy dissipation type,the joint prestress loss is small,ductility is good,and the strength degradation is slow.On the basis of the test,this paper combined relevant data at home and abroad,and referred to relevant theoretical research on steel nodes,reinforced concrete column-steel beam nodes and reinforced concrete nodes.The stress mechanism and failure pattern of composite node of reinforced concrete column-composite beam were analyzed,and the phase of destruction of each node corresponding calculation formula was given,respectively,for the subsequent research of reinforced concrete column-composite beam foundation.