Pull-Out Tests of Headed Studs Embedded in Steel Fiber–Reinforced Geopolymer Concrete

This work experimentally analyzes the behavior of studs, with different head thicknesses and embedded depths, centrally anchored in concrete blocks subjected to the direct pull-out test. Sixteen blocks with dimensions of 400 mm×400 mm×250 mm were cast, four of which were made with conventional concrete (CC), four with steel fiber–reinforced concrete (SFRC), four with geopolymer concrete (GPC), and four with steel fiber–reinforced geopolymer concrete (SFRGPC). Metakaolin was used as a precursor and sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) as activators. The volume fraction of fibers was 1.0%, and the compressive strength was ∼35 MPa. The results were analyzed regarding gain in failure load, displacements, and failure modes. The results showed that the geopolymer with steel fibers can be applied to concrete structures since the elements tested showed superior mechanical behavior to conventional concrete. The SFRC and SFRGPC blocks showed a significant increase in failure load. However, SFRGPC showed higher failure load results than SFRC, and the same behavior occurred between GPC and CC.