Study On Mortise And Tenon Bonding And Sealing For Wood-plastic/Solid Wood Composite Section

Wood-plastic composite(WPC)has the advantages of easy processing,wood feeling and water resistance and insect repellency.Many research and application results have been made in the aspects of doors and windows,floor and decorative section in recent years.However,the shortage of this type of composite is gradually exposed in the application.The construction of wood-plastic/solid wood composite section is proposed to solve this deficiency.But this composite section has a two-layer structure that makes it difficult to connect to the application.To realize the connection of this composite section,the performance of bonding of WPC is studied at first,which is investigated by changing the content of wood.The experimental results show that,the cementation strength of two-component acrylate(AEA)is increased from 0.7MPa of 20% wood to 2.0MPa of 60% wood.But ethylene-vinyl acetate copolymer hot melt adhesive(EVA)cementing strength change is not obvious,changing from 1.7MPa to 2.0MPa in general.The increase of wood power content not only can increase bonding strength,but also reduce production cost and improve the surface texture.Secondly,the available adhesive in the application of mortise and tenon joint of woodplastic/wood composite section is put forward in this paper.The maximum damage power of different adhesive is measured with roughening treat,which is over 2000.And the changes of storage modulus(E')wood-wood and WPC-WPC are compared,which are glued by five kinds of glue adhesion agent by dynamic thermomechanical analysis(DMA).The results show that the E' is associated with the strength of the gel and the form of destruction indoor temperature.The adhesive of polyurethane is not clearly relaxed under test conditions.In addition,the displacement and the process of damage of mortise and tenon joint under loading,the overall load capacity,the failure mode and the damage process of the tenon structure are simulated by ABAQUS.The results show that the stress concentration of mortise and tenon is obvious during load loading.The damage is first seen in the layers of the structure.The load increases damage from the bottom up,and is expanded by the mortise.When the damage value,CSQUADSCRT,reaches 1,stiffness begins to deteriorate and capacity decreases.The simulation analysis shows that the adhesion and the mortise and tenon structure have the function of co-loading,and the maximum destructive capacity is 2076 N.Finally,the sealing problem is discussed in this paper.The contrast sealing experiment is carried out,the study found that the screw has the very good sealing,but the surface damage of wood-plastic/wood must be sealed.