Numerical Modelling of a Novel Joint System for Grid Shells with T Cross-sections

A novel joint system developed for single-layered steel grid shells with T cross-sections is presented in this paper. The joint system is bolted to facilitate quick and easy on-site assembly. First, a solid finite element model was built to investigate the behaviour of the developed joint system. The moment-rotation characteristics of the joint system were determined and the joint strength and stiffness was investigated. Key parameters influencing the behaviour of the joint were studied, such as bolt diameter, pretension, component geometry and normal force. As a second step, free-form roof structures with a span of 40÷80 meters were chosen and analysed with the developed joints. The previously obtained moment-rotation results were used as spring moment-rotation characteristics in beam finite element models. The load bearing capacity of the structures were determined. The results were compared to that of grid shells with rigid joints, and it was shown that the joint system is stiff enough.