Experimental and numerical study on optimization design of stretcher positions

In this study, the withdrawal strength of T-shaped joint was investigated through using Finite Element Method (FEM) and Analytic Method (AM). Firstly, the mechanical properties of wood were measured by conducting the experiment. In addition, the influence of friction coefficient between wood interfaces was studied with various size of contact area, direction of grain and pressure. Then, a mathematical model of oval mortise and tenon joint withdrawal strength was established based on linear elastic mechanics. Subsequently, the withdrawal strength of T-shaped joint was analyzed on the basis of numerical method with Finite Element Method (FEM) software. Finally, with the application of the experimental method, comparison and analysis were made between numerical method and analytic method. The results demonstrated that the consistency level between the numerical method and experiment was 83 %, which is more accurate than that between analytic method and experiment 80 %. As a results, the mathematical model was applicable to calculate the withdrawal strength of mortise and tenon joint which can also meet the engineering requirements of wood construction and wooden products structure design. In addition, the FEM applied in the study was more precise than analytic method while the latter was comparatively simple and convenient. These two methods were capable of evaluating the withdrawal strength of mortise and tenon joint, which can also be applied to structure design and optimization of wood construction and wooden products in order to make the design more scientific and reasonable.