Pull-out strength of an expansion stud anchor in carbon fiber reinforced concrete

• Main Author: Estores, Gilford B.
• Format: text
• Published: Animo Repository 2017
• Subjects: Building materials; Reinforced concrete
• Online Access: https://animorepository.dlsu.edu.ph/etd_doctoral/1341
• Institution: De La Salle University

Carbon fiber reinforced concrete (CFRC) is considered as an innovative structural material because of its better performance characteristics when compared to conventional concrete. Its common applications where expansion stud anchor connection is possible are in slabs on grade, wall panel, curtain walls, and pre-cast elements. The design of this stud anchor in CFRC is of great interest to many structural engineers, however, no model is available as basis for its design. To develop such model, the pull-out strength of an expansion stud anchor embedded in CFRC as influenced by fiber volume content (Vf), fiber length (Lf), compressive strength and tensile strength were studied. Three compression, three tension, and five pull-out CFRC specimens each of different Vf (0.10%, 0.15%, 0.20%, 0.25%, 0.30%) and different Lf (19 mm, 30 mm, 38 mm) were prepared, tested, analyzed, and compared to control concrete specimens at design compressive strengths of 21 MPa, 28 MPa, and 35 MPa. Tests results show that pull-out strength of an expansion stud anchor in CFRC is maximum at Vf = 0.10% and Lf = 38 mm. Among the parameters considered, tensile strength is the most significant contributing factor that could influence the pull-out strength of stud anchor in CFRC. This is further verified numerically by a micromechanics analysis and by a FEM model with good agreement to the observed tensile strength. A response surface methodology (RSM) model was developed to predict the pull-out strength of an expansion stud anchor embedded in CFRC as influenced by the fiber volume content, compressive strength, and tensile strength. Finally, a Modified CCD model which was partly modeled by micromechanics analysis was also developed to predict the pull-out strength of an expansion stud anchor in CFRC.