Railroad blocking problem (RBP) is one of the problems that need an important decision in freight railroads. The objective of solving this problem is to minimize the costs of delivering all commodities by deciding which inter-terminal blocks to build and by specifying the assignment of commodities to these blocks, while observing limits on the number and cumulative volume of the blocks assemble...

In rail transportation, there have been several attempts to determine the best routes for shipments (a number of cars with the same origin-destination) through the network. Shipments enter into several intermediate yards on their routes to separate and regroup shipments into new trains. Most of time, every entering into a yard includes excessive delay for shipments; therefore it is an ideal pla...

On major domestic railroads, a typical general merchandise shipment, or commodity, may pass through many classification yards on its route from origin to destination. At these yards, the incoming traffic, which may consist of several shipments, is reclassified (sorted and grouped together) to be placed on outgoing trains. On average, each reclassification results in an one day delay for the shi...

In wagonload traffic, a production form in railway freight traffic, small groups of wagons have to be transported. In order to decrease transportation costs, wagons from different relations are consolidated. In railyards trains can be separated and rearranged to new trains. The costs arising from this process, which is called reclassification, must be balanced with the transportation costs. The...

This reasearch studies ACO algorithms for the switch engine scheduling in a Railroad Yard. The cars are moved individually or grouped into blocks by a set of locomotives called switch engines which are dedicated to moving around the cars in the yard. The need for moving comes from the fact that the arriving trains are disassembled into blocks of cars, undergo some operations like, loading , unl...

Railroad transportation of hazardous materials did not receive as much attention as highway transportation in the academic literature, although comparable volumes are shipped via these two transport modes in North America and Europe. In this paper we present an optimization methodology for the railroad tactical planning problem with risk and cost objectives. We determine the routes to be utiliz...