Enhancing the flexural response of RC one-way slabs using low cost fiberglass chopped mat sheets and anchors

This study experimentally evaluated the effectiveness of Carbon Fiber Reinforced Polymer (CFRP) and Fabric Cementitious Matrix (FCSM) sheets in enhancing the structural performance of one-way reinforced concrete slabs under three-point bending. Fourteen slabs were tested, considering key variables such as the number of FCSM sheets, type, size, and spacing of anchors to mitigate debonding. Results revealed that slabs strengthened with FCSM sheets and epoxy anchors demonstrated peak capacity improvements of up to 151 %, while mechanical anchors yielded a peak improvement of 95 %. Epoxy anchors also enhanced energy dissipation by up to 222 %, surpassing the 76 % maximum improvement observed with mechanical anchors. However, slabs with more than two FCSM layers required robust anchorage systems to maintain increased capacity without significant drops due to debonding. Slabs with epoxy anchors showed higher peak capacities but were more prone to abrupt post-peak losses than those with mechanical anchors. These findings underline the critical role of anchor type and configuration in optimizing the flexural and energy dissipation performance of strengthened slabs, providing valuable insights for sustainable and effective retrofitting strategies. Finite element modeling of slabs strengthened with FCSM, assuming no debonding, was carried out using ATENA software. The adopted modeling approach yielded slightly overestimated predictions of ultimate loads. As this represents initial research in the field, further investigations are recommended to develop more accurate and refined constitutive laws for FCSM to enhance the reliability of FEM simulations.