Effects of rust spots on load‐bearing capacity, deformation, and cracking evolution of prestressed concrete cylinder pipes

Inspection of a prestressed concrete cylinder pipe (PCCP) project revealed unusual rust‐like surface imperfections, and their impact on the load‐bearing capacity remains uncertain. In this study, a three‐edge bearing test was conducted on a PCCP with rust spots. Subsequently, finite element models of the intact PCCP and the PCCP with multiple rust spots were developed to examine the structural response throughout the overloading process. The experimental findings showed that the existing rust spots had a negligible effect on the load‐bearing capacity of the PCCP structure. In addition, the numerical results indicated that the PCCP had distinct eccentric loading phenomena in the crown, invert, and springlines under external pressure. Rust spots would exacerbate the eccentric loading phenomenon and result in localized stress concentration in their vicinity. However, both the numerical models reached only the serviceability limit state. The intact model had a serviceability limit state of 128% P c , whereas the model with multiple rust spots had a serviceability limit state of 100% P c . Thus, the PCCP demonstrated substantial resistance to external pressure.