Experimental and numerical study on the cyclic performance of the gear-bolt semi-rigid joint under uniaxial bending for free-form lattice shells

To study the cyclic behaviour of a novel gear-bolt semi-rigid joint, quasi-static tests were conducted on seven full-size specimens. The key parameters of the gear-bolt joint investigated in this test include the gear-bolt diameter, number of teeth, and tooth depth to gear-bolt diameter ratio (t/d). A detailed research is carried out to study the effects of these parameters on the hysteresis curves, skeleton curves, degraded characteristics, ultimate capacity, energy-dissipation capacity, and failure mode. The experimental results showed that the hysteresis performance was enhanced with the increasing of number of teeth, gear-bolt diameter, and t/d. In particular, the hysteresis curves were fuller with higher number of teeth; however, an excessive number of teeth should be avoided as it would lead to a brittle rupture of the teeth. The ultimate capacity increased with the increase in the gear-bolt diameter and t/d. of accurate finite-element (FE) models of gear-bolt joint considered the geometry and material nonlinearity was established, and the accuracy of the FE mode was verified by comparison of the computation with test results. (C) 2018 Elsevier Ltd. All rights reserved.