Ductility and performance assessment of glass fiber-reinforced polymer-reinforced concrete deep beams incorporating cementitious composites reinforced with basalt fiber pellets

The purpose of this study is to assess the feasibility of using a non-metallic basalt fiber (BF) pellets to enhance the ductility of glass fiber-reinforced polymer (GFRP) reinforced concrete deep beams. In addition, the ability of BF pellets to supplant conventional web reinforcement was evaluated. To achieve the goals of this study, seven large-scale concrete deep beams reinforced with GFRP headed-end bars were constructed and tested to failure under three-point loading over a span of 1390 mm. The beams had a rectangular section of 250 x 590 mm with overall length of 2100 mm. Experimental variables included the volumetric percentage of BF pellets and transverse web reinforcement. The addition of fibers improved the post-peak behavior by increasing the ductility index by more than 50%, when compared to the counterpart control beam. The results provide support for replacing conventional web reinforcement in deep beams with a layer containing BF pellets in the tie zone.