Researchon The Mechanical Performance Of Beam-column Joints Of Glulam Frame

In the context of sustainable development and assembly construction of building structures,wood structures are more and more widely used because of wood is a recyclable green building material.At present,the bolted connections of steel plates in timber is widely used due to its convenient construction and simple force.The bolted connections of the steel slab mainly uses the horizontal grain of the wood to bear the force,and the horizontal grain of the wood is low in strength,and its failure mode is mainly the horizontal splitting of the wood.Due to wood-structured buildings have gradually developed from the original low-rise buildings to the current mid-to-high-rise buildings,higher requirements have been placed on the beam-column joints.For this reason,the research on the innovative connection mode of beam-column joints is particularly necessary.Considering the characteristics of low-strength and easy cracking of the cross-grain of the steel filler plate joints,this paper proposes two creative beam-column connection methods that use the square steel pipe connection joints that make full use of the strength of the wood along the grain and the steel filler plate connection joints with flanges.In order to study the mechanical performance of the innovative connection form of wooden beam-column joints,the finite element software ABAQUS was first used to simulate and analyze the existing experimental research to verify the feasibility of the model.Based on the verified finite element model,the exterior joints and interior joints using the square steel tube and flange filler steel plate connection method are further analyzed.Considering the design parameters of the end plate thickness,the length of the connections,the arrangement of bolt and the stiffening,16 models were established for the square steel tube connections;and 4 models were established only considering the stiffening setting for the connection method of flange steel slab.Subsequent pseudo-static simulation analysis was performed on all models,focusing on the hysteretic performance,bearing capacity,stiffness and energy dissipation capacity of the connections.The research results show:(1)The square steel pipe connection joints make full use of the mechanical properties of the gluing wood along the grain.The strength and stiffness of the joints are significantly improved,but the energy dissipation capacity of the joint is poor;(2)The thickness of the end plate and the length of the joint have a significant impact on the performance of the joints.The stiffness and bearing capacity of the joints tend to increase with the increase of the thickness of the end plate and the length of the connections;(3)The arrangement of bolt has little effect on the mechanical properties of the square steel pipe connections;(4)The use of stiffeners for connections can speed up the force process of the joints,and significantly improve the stiffness and bearing capacity of the joints;(5)Adding flanges on the filler steel plate connector can reduce the tensile stress of the glulam cross grain and inhibit cracking of horizontal grain of the wood,and steel filler plate joints with the flange have good ductility and energy consumption performance.