Development of a Reliability-Based Design Procedure for Rigid and FlexibleAirfield Pavements

摘要

The current U.S. Army Corps of Engineers thickness design procedures for rigidand flexible pavements are deterministic in nature; i.e. they use one value (typically the mean value) for each of the design parameters and essentially ignore the inherent variability of the design parameters during the design process. Variability in the design parameters, such as the California Bearing Ratio (CBR) of the subgrade in flexible pavement design, for example, may be recognized during selection of the one design value, but the effects of a subgrade having a relatively consistent CBR versus one that doesn't cannot be assessed. The use of probabilistic techniques to characterize the variability of the pavement design parameters, such as with the standard deviation or coefficient of variation (CV) of the parameter, and translated into an estimated reliability for a particular design, would enable an engineer to more effectively design a pavement for a particular application. These tools would also allow the engineer to evaluate the effects of different degrees of variability in a pavement system, perhaps those determined from quality control and assurance testing during pavement construction, on the reliability of the design, from which appropriate adjustments to compensation for the builder could be more readily quantified. The Corps of Engineers primarily uses two design procedures for both rigid and flexible pavement design for airfields. The two rigid pavement design procedures are based upon the same performance data taken from the trafficking of pavement test sections constructed for that purpose.