Analysis of the mechanical behavior of bolted joints with slotted-in steel plate considering the move path of rotation center for single-layer timber reticulated shell

The mechanical behavior of the bolted joints with slotted-in steel plate plays an important role in maintaining the stability of single-layer timber reticulated shell, yet methods to estimate the mechanical behavior of the bolted joints still remains to be improved. Assuming that the ductile failure of the bolted joints and the compressive failure of the glulam beam end occurred, the move path of the rotation center was obtained through theoretical derivation and used to determine the ultimate moment and rotational stiffness of the bolted joints. The equations for calculating the ultimate moment of the bolted joints were derived based on the European Yield Modes, t. Moreover, employing the beam on elastic foundation theory, a simplified equation of slipping stiffness was obtained and used to calculate the rotational stiffness. Experimental investigations on bolted joints for single-layer timber reticulated shell were conducted to verify the accuracy of the proposed theoretical methods. The results showed the rotational stiffness and ultimate moment obtained from theoretical calculation were consistent with the results of experimental tests. Furthermore, by calculating the move path of the rotation center, it was found that the rotation center started from the geometrical center of bolts at earlier loading stage and moved towards the compressive region of the glulam beam end with the increase of the external force. And the moment-rotation curves predicted by the linear model was in good agreement with the moment-rotation curves obtained from experimental tests, showing a convenient and reliable way to the design of bolted joints for single-layer timber reticulated shell.