Re-anchoring of failed in-situ grouted post-tension anchor rods with high rod to duct area ratios
Published: 2024
Publication Name: Engineering Structures
Publication URL: https://doi.org/10.1016/j.engstruct.2024.118589
Abstract:
An experimental program was conducted that simulated an internal rod failure to review re-anchoring ability, transfer length, and residual bond strength of grouted post-tension anchors with high rod to duct area ratios under in-situ conditions. Additionally, a theoretical model founded on interference fit, initial assumptions, and debris wedging was expanded to include a concrete to pipe interface. The experimental program included three full scale concrete specimens, whose length, annulus space for grout, and anchor diameter were nearly identical to existing anchors within dams in California. The specimens were instrumented along the anchor and concrete to capture strains in the longitudinal and transverse directions, the values of which, were compared against the theoretical model and found to be in good agreement along with the measured transfer length values. The debris wedging ratio found was consistent across the specimens and closely resembles the ratio captured in a similar study by the authors.