The experience of New Jersey with pavements, like that of many other states, goes back to the last century. Highways constructed early in this century are still in service. During these extensive service lives, several maintenance and rehabilitation activities were applied to keep the pavements in good condition. These activities ranged from patching to full reconstruction. Also, most of New Jersey pavements have been widened at least once. With all these factors, it is difficult to identify the limits of homogeneous sections that should receive the same rehabilitation treatment. In 1996, the New Jersey Department of Transportation started a limited network level falling weight deflectometer (FWD) program. This program has short- and long-term goals. The short-term goals include identifying the limits of homogeneous sections (sectionalization), assessing the pavement structural capacity, estimating the remaining service life, and determining the future rehabilitation needs. The long-term goal of the project is to use the FWD measurements for the ongoing development and refinement of the models used to predict remaining structural life for use in economic evaluation models. The procedure followed to achieve the short-term goals of the project and an outline of the findings of the project are summarized.

Traffic loading, environmental conditions, subgrade soil, and construction and maintenance quality are among the factors that influence pavement performance. Environmental conditions can have a particularly significant impact on the performance of low-volume road pavements. It is intended that the Strategic Highway Research Program performancegraded asphalts ensure that an asphalt binder is selected based on in-service pavement conditions. This new system will enable designers in Ontario to account for differences in climatic conditions and traffic loading, which vary between the southern and northern areas of the province and have always posed a challenge to pavement designers. A deflection-based method was originally developed in the 1970s based on the AASHO road test and the Brampton road test. The design system incorporates elastic layer analysis to determine pavement response. It uses cumulative equivalent single-axle loads, subgrade type, and layer thickness to determine the most effective design. The design system has been recently updated and recalibrated to separate the environment and traffic effects on performance. In effect, the total pavement performance is the cumulative effect of the damage due to the environment and the damage due to traffic. Hence, the differences between roads in southern and northern Ontario can be quantified. The system calculates roughness either in terms of the international roughness index or the riding comfort index, or in terms of performance as a pavement condition index. The mechanistic-empirical performance model can be recalibrated to apply to conditions outside of Ontario. Examples show the relative deterioration and performance curves for various design situations.

The ability to systematically collect and record as-built data for pavement layers benefits highway departments in many aspects. A well-established database of as-built pavements provides a tool for maintaining an up-to-date corporate record of the physical pavement structures, keeping track of unit construction costs, and reducing the amount of pavement excavations during pavement investigations. A reliable as-built database also provides inputs for falling weight deflectometer analysis and calibrating pavement performance models in pavement management systems (PMSs). A task within the development of the second-generation PMS for the New Jersey Department of Transportation is to review and analyze the existing pavement as-built database for completeness and quality. A computer program was developed to scan and categorize the as-built data into five status levels: complete, partially complete—missing original construction data, partially complete—missing recent rehabilitation data, questionable data, and no data. The results of this analysis can be used to recommend improvement for the data-collection process and to guide further investigations, such as coring and ground penetration radar tests. The general approach used in the analysis is described, data status levels are defined, results for distribution of the pavement as-built data are provided, and the significance of the analysis for PMSs is discussed. Recommendations for improving completeness and quality of the pavement construction history database also are provided.