Study On Mechanical Behavior Of The Laminated Veneer Lumber Beam-column Joints

In recent years, the light wood construction house was known very well by the people, and they also more like wood frame residential buildings.but facing the fact of the shortage of timber resources, it is difficult to support the development of wood structure.This article describes a new engineered wood:veneer Board laminated wood (Laminated veneer lumber, LVL). The flexible material with high strength, specifications, stability, good vibration damping performance, economy, higher flame resistance and weather resistance are much better than wood.If the material can be widely used in our country, it can effectively promote the development of timber structures.The design of the nodes is critical in wooden architecture,In various form of nodes the bolt connection has a reliable,artistic feature,and the capacity,stiffness of the Glued-in rods joints are quite large,they are widely used in modern timber structures,however,in our nation,the research on connecting joints of timber structure is rare,the accumulated experience for blot connections and glued-in rods joints designing is also rare,the research on dynamic hysteresis of them is almost blank,and it is extremely lacking in raw data.For those reasons,it’s particularly urgent to make research on the stress performance of the bolt connections and glued-in rods joints of timber structures.In this paper,by the method of combining of experimental research and theoretical analysis and finite element analysis, we will focus on the stress response of wood-steel-wood bolted joints and glued-in rods joints under unidirectional load and cyclic loading.The main research contents and achievements are as follows:(1)The mechanical properties of the joints of timber structure is closely related to its material properties, so this article firstly makes research on material properties of LVL and bolts, mainly including LVL density, moisture content,anti-shear of LVL, anti-compressive strength of down-grain, the bearing strength of pin slot, anti——flexural strength of bolts,and so on.(2)Make a test on three groups of LVL joints, it was a monotonous and cyclic loading test. The main trial is about damage mechanism and form, hysteresis curve, skeleton curve, capacity of energy dissipation, stiffness degradation, and other hysteretic performances of dynamics under the reserved cyclic loads, studying the effects of the change of the structural form on dynamic performance of the joints.(3)According to relevant references,the stress mechanism of three nodes were analyzed,then the flexural capacity of three nodes were derived from the theory,the theoretical and results agree well with the experimental results.(4)Using finite element analysis software ABAQUS to make three dimensional solid modeling analysis on three groups of wood structure joints, skeleton curve and stress nephogram of simulation results have conformities well with the experimental values.