Research On Mechanical Behavior Of Metal-plate-connected GluBam Floor Trusses

In the light truss system,in contrast with other ways of node connection,since metal plate connection has the characteristics of being good and reliable in structure performance,fast and convenient in construction and the like,it is more widely used in light wood truss design.Since GluBam is a type of new green construction material whose mechanical properties could be compared favorably with wood materials.The research on the mechanical behavior of metal-plate-connected GluBam floor truss plays an important role in promoting the application of glue laminated bamboo structure in the construction field.Floor truss as an important part of the modern bamboo structure,its bearing capacity affects the structure performance directly.In oder to provide the reference for the Glue laminated bamboo floor truss design and application,in this paper,the mechanical behavior of metal plate connected GluBam floor trusses were tested.Firstly,by referring to "Code for design of timber structures" GB50005-2003 and"technical code for light wood trusses" JGJT 265-2012,this paper,by virtue of the tensile test,has examined the tooth strength of metal-plated connected glued laminated bamboo joints under ten types of specimens conditions.The results showed that metal plated connected GluBam joint compares with metal plated connected wood joint has a higher single tooth strength under the most conditions.Secondly,by referring to the recommended floor load in relevant foreign light truss design manual and code,the author designed two different span respectively 3m and 5.6m metal plate connected GluBam floor trusses and checked the loading capacity of members and metal plate connection joints based on the single tooth strength by the tensile test.Then,two groups of GluBam truss specimens,respectively 3m span and 5.6m span,were tested by the static loading test,each of them had 4 specimens.Through the test,the ultimate bearing capacity,load-displacement curves,strain of members and failture modes were obtained.Meanwhile understand the possible destruction model of truss.The test results showed that the GluBam truss is a reliable and environmental structure with sufficient strength reserve.Specimens failure mode is brittle failure,the splice joints lose efficacy when specimens were broken.Finally,finite element analysis software SAP2000 was used to simulate and analyzed the GluBam truss,and compared the analytical results with the test result of the displacement of main nodes and the strain of several members under the elastic stage.Overall,the analytical results were in a good agreement with the experimental results.