The application of pseudo-ductile cementitious composites in the anchorage zone of post-tensioned concrete members

Abstract

In China, fiber reinforced concrete (FRC) has been employed in practice for many years. In this paper, after a brief introduction to the current status of FRC applications in China, we will focus on recent research related to the use of pseudo-ductile cementitious composites (PDCC) to resist tensile splitting at the anchorage zone of post-tensioned concrete members. To simulate the situation at the anchorage zone, rectangular concrete columns were loaded under concentrated compression. Tests were performed on members made with (i) plain concrete, (ii) plain concrete and steel stirrups, as well as (iii) concrete with PDCC at the anchorage zone. According to the test results, PDCC is effective in improving the ultimate load under concentrated compression as long as failure is governed by tensile splitting. In some cases, it is found to be more effective than the steel stirrups. However, when the PDCC compressive strength is much lower than that of the concrete, compressive crushing failure may occur instead of tensile splitting, and the load capacity will then be decreased. For members that fail in splitting, a simple design method is proposed and the predicted failure load provides a close estimate of the experimental value. Based on the present study, the use of PDCC to replace all or part of the steel stirrups in the anchorage zone is proved to be feasible.