Effect of various factors related to the bond-type anchorage system on tensile performance of carbon fiber-reinforced polymer strand cables

Steel strands, which are most frequently used as internal/external tendons of prestressed concrete (PSC), are highly susceptible to corrosion, which degrades the structural stability of the PSC structures. Studies are underway to utilize carbon fiber-reinforced polymer (CFRP) strands in PSC structures as tendons to achieve structural performance comparable to that of existing steel strands, with the additional feature of corrosion resistance. However, such applications of CFRP strands require the accurate identification of the intrinsic properties of the material. This study conducted an analysis to establish a test method using bond-type anchorage that can evaluate the intrinsic properties of CFRP strands by setting several factors related to the bond-type anchorage system as variables. Tensile tests were conducted on the CFRP strands after fabricating the specimens according to the variables of the bond-type anchorage system (shape of the CFRP strand located inside the steel pipe and type of internal filler material). In addition, the compressive strength was measured to determine the mechanical properties of the cementitious filler materials. Based on the experimental results, the load-displacement curves, stress-strain curves, fracture shapes, and tensile strengths of various cases of CFRP strands were analyzed. The results of the study revealed that the split-strand CFRP fabricated with CP0.25 mixture as the bond-type anchorage system had the ability to fully obtained intrinsic tensile properties.