Rotational performance of semi-rigid plate-type joints for reticulated shell structures composed of plate members

Abstract

Manufactured by laser cutting technology with planar steel plates, the plate members have significant advantages in efficiency, customization, and transportation. These advantages make the plate members suitable for building small or medium-span curved reticulated shell structures. The plate members have been adopted in a novel reticulated shell structure with stiffening methods for resolving local buckling issues. In this type of structure, the semi-rigid plate-type joints are used to connect plate members. The previous study indicated that the rotational stiffness of plate-type joints has a great impact on structural stability. To investigate the rotational performance of the semi-rigid plate-type joints, a comprehensive study has been conducted in this research. Experimental tests were performed on a total of 12 specimens to obtain the moment-rotation responses of the joints. Four phases of the failure process were observed in the tests, namely, the linear elastic phase, slipping phase, hardening phase, and failure phase. The influences of joint width, joint thickness, and bolt diameter on the rotational performance are revealed by the experiments. Then, a refined finite element (FE) model was built and validated by the experimental results. This validated FE model clarified the failure mechanism of joints from the perspective of stress development and contact condition. Furthermore, theoretical formulas were established to calculate the key characteristics of the moment-rotation response, which is proved to have acceptable accuracy in predicting the rotational performance of joints. The conclusions of this study may provide a valuable reference for the structural stability design of reticulated shell structures composed of plate members.