The effect of street geometrics and signalization are discussed in terms of travel time, which is defined as the time of travel through a street section averaged overall drivers and all specified time periods within a prescribed class. This is the key factor in the evaluation of traffic operations. Travel time is shown to be significantly and reliably related to volume, given specific street section characteristics. An extensive sample of urban arterial street field survey data collected through a collaborative effort of state and local agencies, is employed to study the dependence of the travel time-volume relationship to the geometrics and traffic control factors. The principal variance-producing factors in the study sample are identified. A major result of the study is the determination of a set of general prediction curves by means of which the travel time-volume relationship can be estimated from knowledge of the characteristics of given specific streets. The application of the travel time results to the evaluation of traffic operations is indicated.
Abstract