Forecasting Serviceability Loss of Flexible Pavements (57-1F)

Pavement performance data collected in Research Project 2-8-62-32, "Extension of AASHO Road Test Results," are analyzed in this study. Serviceability loss of three flexible pavement types due to fatigue, swelling, shrinkage and thermal cracking are correlated to many environmental, traffic, time, design and construction material variables. A "two-step constrained select regression procedure" is developed to find the functional relationships. A sensitivity analysis method is developed to examine the effect that each variable has on pavement serviceability loss. Stochastic reliability concepts are applied to evaluate the expected value and variance of the serviceability loss.