Iran Khanzad - MSc Grad., Department of Civil and Environmental Engineering, Tarbiat Modares University, Tehran, Iran
Amirali Zarrinmehr - Ph.D Candidate, Department of Civil and Environmental Engineering, Tarbiat Modares University, Tehran, Iran
Seyedehsan Seyedabrishami - Assistant Professor, Department of Civil and Environmental Engineering, Tarbiat Modares University, Tehran, Iran
Mahmoud Mahmoud - Professor, Department of Civil and Environmental Engineering, Tarbiat Modares University, Tehran, Iran

Establishing a network of transit routes with satisfactory demand coverage is one of the main goals of transit agencies in moving towards a sustainable urban development. A primary concern in obtaining such a network is reducing operational costs. This paper deals with the problem of minimizing construction costs in a grid transportation network while satisfying a certain level of demand coverage. An algorithm is proposed following the general idea of constructive algorithms in related literature. The proposed algorithm, in an iterative approach, selects an origin-destination with maximum demand, generates a basic shortest-path route, and attempts to improve it through a route expansion process. The paper reports the scenarios and further details of the algorithm considered for expanding a transit route in a grid network. A random 6×10 grid network is applied to report the results. The results support that application of the proposed algorithm notably reduces the operational costs for various amounts of demand coverage.

Transit routes, grid transportation network, demand coverage, operational costs