Experimental study of deconstructable bolt shear connectors subjected to cyclic loading

An experimental study of deconstructable steel-concrete shear connectors using bolts under a low-cycle high amplitude loading protocol is undertaken to investigate the effect of the concrete compressive strength, bolt size and its grade and size of clearance between the precast concrete slab and bolt on the load-slip response. To characterise the cyclic performance of the shear connectors, the ductility, strength degradation and absorbed energy are evaluated for all specimens. The experimental campaign includes twelve deconstructable shear connector specimens which were constructed and tested to failure. The failure modes involved severe concrete crushing, fracture of the bolt connectors, bolt bending and fracture, and bolt bending. In addition, three separate specimens were constructed and tested under monotonic loading and the results were compared with their cyclic test counterparts. The results obtained from the experiments show that the ultimate shear load capacity of the deconstructable steel-concrete shear connectors under cyclic loading was considerably less than that under monotonic loading. A structural model comprising of two parallel springs is also described and fitted to the experimental results to represent the load-slip response of the examined shear connectors. (c) 2021 Elsevier Ltd. All rights reserved.