Analytical model and rotational performances of dovetail mortise-tenon connection at the column head of traditional wooden frame

Abstract

This paper presents an analytical model of dovetail mortise-tenon (DMT) connection at the column head of traditional wooden frame. Firstly, the characteristic of geometric deformations at the tenon is revealed based the geometric model when the tenon rotates clockwise and anticlockwise, and the analytical expressions for these deformations are given. Then, the extension deformations are obtained based the numerical model, these extension deformations at the surface of the mortises are fitted by the two-dimensional functions in two rotational directions. Finally, the analytical model of DMT connection is derived based the stress distribution at the tenon when it rotates in two directions, and the proposed model agrees well with the corresponding numerical model. Moreover, the effect of parameters including geometric dimensions and frictional coefficient on the rotational performance of DMT connection is studied based two models. The results showed that the difference of the two models is magnified as the friction coefficient increases, the resisting moment of the DMT connection is proportional to the cube of height of tenon and the length of tenon. More refined extension deformation analysis of mortise is needed for general expression of the DMT connection, since the extended deformation of the mortise varies as the inclination angle of the side surface of tenon changes.