Development of a new asphalt pavement performance prediction model

The Ontario Pavement Analysis of Costs system has been in service for Ontario asphalt flexible pavement design and performance prediction since the early 1970s. It uses a deflection-based deterministic model for selecting the best pavement structural design alternative in terms of pavement functional and structural performance and the total life-cycle costs. However, because of the existence of uncertainties and variations in pavement design variables and parameters in the pavement deterioration models, it is not adequate to apply deterministic models to all situations of pavement management. It is therefore necessary to predict pavement performance by employing probabilistic-based models. In this paper, a new concept of system conversion between a deterministic model and a probabilistic model is discussed first. A method by which a deterministic pavement performance prediction model, such as the Ontario asphalt pavement deterioration model, can be converted into a probabilistic model is presented. A transformed probabilistic model is constructed by generating a set of time-related nonhomogeneous Markovian transition probability matrices, which is determined by Monte Carlo simulation. Each of the transition probability matrices characterizes the pavement deterioration rate for the given pavement age and traffic characteristics. A Bayesian technique is then employed to update the predicted pavement performance in terms of the pavement condition state vectors and the expected pavement condition state values by integrating additional information such as the actually measured performance data of the pavement.