Study On Seismic Behavior Of Tenon-mortise Joint Of U-shaped Steel-concrete Composite Beam And Steel Plates Shear Wall

In order to adapt to the requirements of domestic construction industrialization(PC fabricated),The combination of U-shaped steel-concrete composite beams and reinforced concrete composite slabs and the outer steel plate shear wall(or double steel plate shear wall)are gradually applied in multi-story buildings due to the exemption of formwork support.However,the current researches are mainly concentrated in the aspect of the shear wall,external U-shaped steel-concrete composite beam,external U-shaped steel-concrete composite beam-frame column joints,etc.There are few researches on the external U-shaped steel beam-encased steel plate wall joints.This paper refers to the traditional wood-structure tenon-mortise connection method and combines the clad steel plate shear wall and the clad U-shaped steel composite beam to propose a U-shaped steel-concrete composite beam cald steel plate shear wall tenon-mortise joints.In this paper,a pseudo-static test on two full-scale U-shaped steel-concrete composite beams clad steel plate shear wall tenon-mortise joints are carried out to study the bearing capacity,ductility,the energy consumption ability and the destruction mechanism of U-shaped steel-concrete composite beams clad steel plate shear wall tenon-mortise joints.The finite element software Abaqus was used to numerically simulate the U-shaped steel-concrete composite beam clad steel plate shear wall tenon-mortise joints.The main conclusions are as follows:(1)In positive loading,the failure feature of the tenon-mortise joints is based on the tearing of the U-shaped steel beam web and the lower flange plate at the root of the U-shaped composite beam.In negative loading,the failure feature of the tenon-mortise joints is based on steel bar connected with steel plate shear wall in the concrete flange plate separating from the wall and U-shaped steel beam web buckling at the root of the U-shaped composite beam.(2)Increasing the anchor length of mortise-and-tenon joint on the basis of anchor length of 500 mm has no obvious influence on the stress characteristics of mortise-and-tenon joint.The positive and negative bearing capacity of tenon-and-mortise joint with full-length anchor length is 6.0% and 8.8% higher than that of joint with anchor length of 500 mm,and its ductility and energy dissipation capacity are slightly lower than that of a tenon-and-mortise joint with anchor length of500 mm.(3)The ultimate bearing capacity of the finite element simulation and the test specimen is close,and the bearing capacity error is within 5%.The development process and position of the damage of the concrete flange plate in the finite element model,the distribution law of the reinforcement stress in the concrete flange plate and the distribution of the stress in the anchored U-shaped steel beam are consistent with with the observed phenomena and test data.(4)Parameter analysis of concrete strength and steel strength is carried out,and it is concluded that the bearing capacity of tenon-and-mortise joints increases with the increase of concrete strength and steel strength.Combining the test results and finite element analysis,the measure of strengthening the connection strength of the steel bars connected with the clad steel plate shear wall and setting stiffeners in the plastic hinge area of the U-shaped steel beam is proposed to improve the buckling capacity of the U-shaped steel beam web.