Quasi-static cyclic behavior of CFRP-confined geopolymeric composites

The utilization of geopolymeric composites can considerably promote sustainability in the construction sector due to their low carbon footprint. In this work, an experimental study was performed to investigate the quasi-static cyclic behavior of geopolymeric composites confined by carbon fiber-reinforced polymer (CFRP). In total, 40 CFRP-confined geopolymeric composite columns were fabricated and tested. The primary variables included the matrix composition (i.e., slag contents of 0% and 10%), type of confined material (i.e., mortar and concrete with recycled aggregate replacement ratios of 0%, 50%, and 100%), and the load pattern (i.e., cyclic loading with a single cycle and cyclic loading with repeated cycles). Careful examination and analysis of the experiment results led to a series of conclusions regarding failure patterns, stress-strain behaviors, and characteristics under ultimate conditions. In addition, discussions were provided concerning the effects of the primary variables on the key characteristics of the stress-strain curves, which included plastic strain, residual and reloading moduli, and stress deterioration for the envelope and internal cycles. In addition, the prediction results by the existing models for fiber-reinforced polymer (FRP)-confined conventional concrete were compared with the test results to assess their applicability for CFRP-confined geopolymeric composites.