Research On The Mechanical Behavior Of Splicing Connections In Glulam Members

With the application and development of the modern technology of glue laminatedtimber structures, more and more large span, multi-storey buildings begin to appear in themodern glulam architectures. The connections tend to undertake large bending momentsand shear forces when the load is applied, great rigidity is needed in order to meet thedesign and use requirements, when the traditional mortise and tenon connection as well asordinary pin connection and other metal connections have been unable to meet the designrequirements. Slotted-in steel plate bolt connection which is simple, artistic, reliable andeasy to install, etc. and has a high carrying capacity and good ductility, has been widelyused in the connections of modern wood structures.The metal connection of modern glued-laminated timber structures has typicalsemi-rigid characteristics, which is between the pinned connection and rigid connectionand has the common characteristics of them both, that is either rotating or undertaking thebending moments. The change of stiffness of the connection is non-linear, that is, thestiffness decreases gradually as the load increases. The structure can behave morereasonably under external loads (especially lateral loads) if taking account of this characterinto design, so the amount of material utilization decreases as a result. In addition, thestructural splicing connections can have good ductility and hysteretic characteristics in theuse of appropriate form and parameters of the semi-rigid connections, so that the structuralsystem can have good deformation capacity and seismic performance. Therefore, thedetermination of semi-rigid characteristics of the glued-laminated timber structuralconnections, that is the M-θ relationship, is particularly important.This paper mainly studies the load and displacement relationship of the slotted-in steelplate bolt connections in modern glulam structures when applied lateral loads. Thedisplacement of connections is composed of two parts, namely, the deformation of the bolt, and the deformation of the wood with respect to the bolt (deformation of wood and boltsunder pressure against each other). Based on the mechanics of materials and mechanics ofelasticity and plasticity, analysis is made of the whole deformation process of the slotted-insteel plate connection with one bolt under lateral loads in use of the principle of virtualwork and unit load method, and the deformation relationship of each part is given which isin good agreement with the experimental results. The research results can provide areference for the processing, design and application of modern wood structures.