Joseph Craus

A REVISED METHOD FOR THE DETERMINATION OF PASSENGER CAR EQUIVALENCIES

Abstract The operating characteristics of trucks and buses differ significantly from those of passenger cars. The former travel more slowly and occupy more space than do the latter. These are the two most prominent reasons for the need to determine the equivalencies of the large-size vehicles in terms of passenger cars, since passenger car equivalencies (PCE) are required for carrying out highway capacity calculations. This paper reviews and discusses the current approaches to such a determination, and then suggests and evaluates a revised method. A direct comparison with current practice is also presented.

EFFECTS OF SOME AGGREGATE AND FILLER CHARACTERISTICS ON BEHAVIOR AND DURABILITY OF ASPHALT PAVING MIXTURES

A summary of some of the findings obtained during a series of research projects aimed to select, define, and evaluate the significant aggregate and filler properties and relate them to the behavior of bituminous concrete is presented. A concept and test method suggested for an objective quantitative evaluation of the geometric irregularity of aggregate particles (shape, angularity, and surface texture combined) in a wide range of particle sizes are discussed. The aggregate parameters were found to be significantly correlated to the physical properties and mechanical behavior of the bituminous mixtures composed of the aggregates tested. Research work and findings related to a special evaluation of important physicochemical properties of the filler and their significant effect on the immediate properties and the long-term durability behavior of bituminous paving mixtures are summarized.