Performance of geopolymer concrete in monolithic and non-corrosive dry joints using CFRP bolts under cyclic loading

This study evaluates the performances of beam-column joints made of geopolymer concrete (GPC). A new dry joint type made of GPC and carbon fibre reinforced polymer (CFRP) bolts was proposed for moment-resisting concrete frames under earthquake loadings. Cyclic loading was applied to test the four specimens which were preparatorily cast by ordinary portland concrete (OPC) and GPC. Compared to monolithic joints, the proposed dry joints showed better performances in the maximum load-carrying and energy dissipation capacity. Additionally, new analytical models to design GPC monolithic and GPC precast joints are proposed. These models well predict the peak loads, main failure modes, failure positions, and horizontal shear strength with a minor variation of 1.3%. The application of GPC promises to effectively recycle a large amount of industrial wastes. Furthermore, the proper design made sure the CFRP bolts survive during the test without brittle failure and shear failure. Therefore, they could be potentially applied in the proposed dry joint to well resolve the corrosive issues in conventional precast joints, as well as satisfying the requirements for construction in sesmic regions.