The effect of temporary obstructions to traffic flow is generally evaluated from the 'delay time' of impeded vehicles. Comparisons of delay time are sometimes very difficult due to varying definitions of delay. In this paper three different time intervals for delayed vehicles are defined: 1. The stopped time. This is the interval between the moment a car arrives at the tail of a queue and the moment a car is able to move again. 2. The time consumed in a defined part of the system (waiting time). - this interval includes in addition to the stopped time, that time interval which is required to cross, for example the point of obstruction. 3. The operational delay time. This is the difference between the time an unimpeded vehicle would have crossed the point of obstruction, and the time the same car actually crosses this point. A formula is developed based on deterministic assumptions, which allows an approximative computation of each of these time intervals. (a) for the covering abstract of the symposium please see irrd abstract no. 224453.
Samenvatting