Effect of lamina thickness on flexural performance and creep behavior of douglas fir glued laminated timber beam

This research presents the effects of lamina thickness on flexural and creep performances of glulam timber. Flexural test results indicated that nonlinear load-displacement curve could be defined as both exponential and power functions. Lamina thickness was not affected to nonlinear curve, especially at initial linear relationship. Slightly different of 2.92% for nonlinear function parameters was obtained. For flexural creep test due to three levels of sustained load for 1,000 hours, only secondary creep stage behaviors without delamination were observed for all glulam timbers while average relative creep was 1.66. Effect of lamina thickness was also not found for creep performance. Finally, creep models have been developed including Bailey-Norton, adjusted Pickel, simplified Pickel, and Dorn models and found that Bailey-Norton and the adjusted Pickel models gave a good correlation with experiment and were the suitable models which could be used to predict long-term flexural creep behavior for various stress levels.

Flexural behavior of osb reinforced wood truss

In this paper, oriented strand board (OSB) on both sides of the wood truss was used to strengthen the wood truss. The flexural behavior of the reinforced wood truss was studied. The results showed that OSB was an effective technical member to improve the flexural bearing capacity of wood truss. Besides, wood truss and OSB can be firmly combined by using glue bonding and screw connections. The screws served only to apply pressure to the glued joint. And the reinforced wood trusses had good synergy and overall stability. The initial bending stiffness and ultimate bending load of the reinforced wood trusses were increased by 203.20% and 234.39% respectively. Ultimate bending load and initial bending stiffness were improved a little by making the wood truss wider. Compared with the traditional wood truss, the reinforced wood truss had the advantages of simple connection mode, less wood consumption, no rolling machine and easy fabrication.