1- Tarbiat Modares University
2- Shahid Beheshti University
Abstract: (7294 Views)
Minimum Spanning Tree (MST) is a mathematical programming problem that may be applied for analyzing transportation network structure and its performance, like its connectivity and link prioritization. Generally, the cost associated with each link is its Free Flow Travel Time (FFTT), however in this paper this concept is developed to the case of a loaded network with capacity constraints and its application to transportation network planning is examined for times of disaster, when the life of many people is involved. In this paper equilibrium travel time for a loaded network is proposed as the link cost and the problem is formulated and solved for Tehran province network. Results show that based on equilibrium travel times, the total cost of MST will have an 8 percent increase from 25973 to 28081 seconds and about 30 percent of the links in the new MST will change. It is also observed that if the MST based on FFTT is used for computing the total cost of the loaded network, the total cost will be 30232 seconds which demonstrates 17 percent increase in cost and 9 percent in error.
Subject:
Earthquake Received: 2011/05/16 | Accepted: 2011/10/20 | Published: 2012/07/3