Capacity Based Operation Planning of Rail Transit Systems: A Case Study for İzmir Light Rail Transit

All railway systems are more reliable than other transit modes for the operating point of view. Because most of the other transit modes are affected from random conditions of the traffic, in which demand-supply balances cannot be adjusted warrantably for the most of operating time. In this case, capacity of the transit mode may not be modulated for the transportation demand. However, especially for metros, capacity analysis is the major and most applied criterion for the operation planning of the transit system, because of the completely controlled traffic conditions. In this study, four different capacity calculation methods are discussed to obtain a suitable approach to operational purposes for rail transit systems. Some of these methods consider not only physical capacity of line and train elements of transit system, but also operational factors such as train control and signaling, station dwells, passenger loading levels and train performance. Also, operational plan of Izmir Light Rail Transit System, which has been operating for three years, is analyzed from achievable capacity point of view rather than design capacity. As a result of the study, some improvable preventions are obtained, especially for the last capacity calculation method. It is seen that, some non productive periods must be neglected for the quality of service and benefits of citizen points of view.