The “predicted performance curve” (PPC): A new structural performance deterioration model for concrete infrastructure

This paper develops a “Predicted Performance Curve” (PPC), a structural performance deterioration curve for concrete infrastructure. The PPC utilizes a reliability-based cumulative Weibull function in order to construct the structural performance curve. The PPC curve starts by constructing an Ideal Performance Curve (IPC) using the Weibull function. Then, an Updated Performance Curve (UPC) is constructed, by introducing at least one piece of available inspection data to the IPC. Finally, after the last inspection, a Predicted Performance Curve (PPC) is constructed. The PPC shows a predicted concrete deterioration curve, and predicts the useful service life. It also can easily consider Maintenance and Rehabilitation (M&R) plans for the structural component. The PPC model is the closest model to represent concrete deterioration, and can be easily developed using scarce inspection (condition assessment) data. In addition, the PPC can also be developed to model a deterioration curve for several structural components as a parallel and series system, hence be extended for the whole infrastructure. The PPC model is applied to transit infrastructure for the Société de Transport de Montréal (STM). The inspection of subway structures is difficult and expensive, hence the PPC proved to be the best method to model the deterioration of the structural components.