Influence of FRP Fan Anchors on the Tensile Capacity of Quadriaxial Fabrics

Undesirable shear failures can be detrimental for the seismic performance of existing RC buildings, particularly at the beam-column joint (BCJ). Experimental tests and analytical studies demonstrated that fiber-reinforced polymer (FRP) materials are effective as local strengthening solutions, enhancing shear capacity and preventing the joint panel shear failures. Furthermore, they have the advantages of rapid and minimally invasive application. Despite these benefits, debonding at the FRP-concrete interface limits their effectiveness to working strains significantly lower than ultimate capacity. Mechanical FRP fan anchors have shown a great potential in avoiding the end-debonding and increasing the strength of FRP systems. However, to date, experimental tests on quadriaxial fabrics, commonly used in the seismic strengthening of BCJs, anchored with FRP fan are missing. This study investigates the influence of FRP fan anchors on the tensile capacity of FRP quadriaxial fabrics. The experimental results of an extensive testing campaign in terms of strength and strain response for anchored and unanchored specimens are presented and discussed along with a comparison with predictions obtained using available capacity models.