Experimental and Numerical Study of the Performance of Existing Prestressed Cylindrical Concrete Pipes Strengthened With Reinforced Concrete or Carbon-Reinforced Fiber Polymer Jackets

Abstract

Prestressed cylindrical concrete pipes (PCCPs) are widely used as precast moduli of water supply systems worldwide. This study experimentally investigates the bearing capacity of 5 PCCPs under internal hydraulic pressure loads to check the capability of specific retrofitting/strengthening schemes to upgrade this bearing capacity. Provided that the prestressing wires are fully active according to design specifications, the original specimen performed satisfactorily for the set internal hydraulic pressure limit of 8.5 bar. Specimens retrofitted with either internal or external CFRP or RC jacketing performed satisfactorily for internal hydraulic pressure levels well above this 8.5 bar limit. A critical factor is, as expected, the loss of prestress. The measured response of the pipes was used to validate a numerical approach aimed at numerically simulating the behavior of the original and retrofitted PCCP pipes. The numerical predictions are in good agreement with the corresponding experimental measurements.