A routing and scheduling model of transportation vehicles for commodities distribution with considering split delivery and multi depots

In recent years, the number of fatalities due to such natural disasters as floods, earthquakes, storms and so on has been increasing. Large damage/fatality dimensions due to such disasters have caused relief to the affected areas and reducing the effects of disasters to be attended to. This necessitates proper management at the time of disaster which includes proper planning, organizing, directing and controlling the required activities. One of the most vital actions of disaster response phase is to provide necessary relief commodities of shelters. In this paper, a three-level network consisting of depots of vehicles, supply centers of relief commodities and shelters has been proposed for simultaneous routing and scheduling of transportation vehicles to distribute relief commodities. In relief commodities distribution operations, the possibility of getting service from each supply center by multiple vehicles, multiple depots for relief vehicles to start and capacity constraint for vehicles and commodities supplies have been intended to. The objective of the proposed model is to reduce the total time required by the transportation vehicles to reach the supply centers and shelters considering hard time windows. Next, to show the efficiency of the proposed model, we select the fourth region of Tehran city as a case study, run the model on it and present solution results. These results show that relief commodities supplies of supply centers affect total time of servicing.