A COMPARISON OF THE SIMULATION MODULES OF THE TRANSYT AND INTEGRATION MODELS

The TRANSYT simulation/optimization model serves as an unofficial international standard against which many measure the efficiency of other methods of coordinating networks of traffic signals that operate at a constant and common cycle length. However, dynamics due to traffic re-routing, the simultaneous operation of adjacent traffic signals at different cycle lengths, the effect of queue spill backs on the capacity of upstream links, and various forms of real-time intersection control cannot be modeled using a static model such as TRANSYT. This has created a unique niche for a more dynamic signal network simulation tool. Before modeling such special dynamic scenarios, there first exists a need to validate the static signal control features of such a model, and to determine if its unique dynamic features still permit it to yield credible static results. This paper therefore strives to achieve two objectives. In the first instance, it attempts to illustrate to what extent the estimates of vehicle travel time, vehicle delay and number of vehicle stops are related when a standard static signal network is examined using both TRANSYT and INTEGRATION. Secondly, the paper strives to illustrate the types of more complex signa