Experimental study of the contact forces and deformations of mortise-and-tenon joints considering the fits and grain orientations of the tenon

A method to measure the contact forces and deformations of mortise and tenon joints based on previous theoretical studies was proposed. The influence of the tenon fits and grain orientations on the contact forces and deformations of the mortises and tenons were studied using this method. The testing method and equations were all introduced in detail. The results showed that the contact force between the mortise and tenon with the tenon in the radial grain orientation was larger than that for the tenon in the tangential grain orientation with the same tenon fit. An exponential relationship between the contact force and tenon fit was found. Also, the deformation of the mortise was 3.6 times smaller than the tenon with a tangential grain orientation and 2.2 times smaller than the tenon with a radial grain orientation.