Experimental Study On Bending And Shear Properties Of SPF Cross Laminated Timber Plate

This paper aims to study the bending and shearing properties of CLT panels.Through experiments,the bending and shearing properties of ordinary SPF(Spruce-Pine-Fir)Cross Laminated Timber(CLT)and SPF Cross Laminated Timber reinforced by implanted steel nails were tested,and numerical simulations were carried out.Find a reasonable reinforcement ratio and transform the common brittle failure of Cross Laminated Timber into ductile failure.Based on the load-displacement curve of the test record,the shear analogy method is used to obtain the bending and shear mechanical parameters of ordinary Cross Laminated Timber and the glulam with steel nails,and calculate the standard value of the bending and shear strength of SPF positive glulam.The main research content is divided into the following parts:(1)Summarize the research results of domestic and foreign scholars on the variable shear performance of CLT plates,including the failure mode,ultimate strength,and bending stiffness of CLT plates.(2)With the three-layer CLT plate as the test object,the bending and shear performance test of ordinary CLT plate and the bending and shear performance test of CLT plate with steel nails were carried out respectively.The results show that the ultimate strength,flexural rigidity and ductility of CLT plates can be enhanced by a certain way of nailing.(3)Using ABAQUS as a numerical simulation tool,compile a user material subprogram representing wood to simulate the existing CLT bending and shear performance test,and verify the correctness of the wood representation based on the subprogram by comparing the test results with the finite element calculation results.(4)Based on the research results of domestic and foreign scholars,a mechanical calculation model corresponding to the test results of the CLT plate after the implantation of the steel nail is assumed,and the limit of the CLT plate after the implantation of the steel nail is deduced according to the assumed mechanical model Strength calculation formula.