Equipment Relay Points

As mentioned, a MIQP is used to determine location points where truck and trailer equipment will be relayed or exchanged, where equipment maintenance can be performed, where information technology facilities can be accessed, where drivers can sleep or rest, where trucks can be fueled, etc. The objective of the mathematical program is to establish relay points on a highway transportation network in such a way to minimize key transportation costs while creating consistent driving tours/routes that have shorter length-of-hauls- compared to typical OTR freight- in order to enhance driver home time and improve long-term driver turnover while maintaining solid driver pay levels. It is crucial that drivers maintain a certain level of weekly driving miles in order to maintain healthy pay since driver pay is usually mileage based. The relay points are also established in such a way to enhance the performance metrics of the

transportation carrier and customer while improving the driving job. From the perspective of the transportation carrier, key items such as line-haul transportation costs, equipment depreciation and maintenance costs, on-time customer service, driver pay, etc. are critical. The customer is also concerned about on-time service and costs. Therefore, the goal is not to improve the driving job at the expense of the transportation carrier and customer. Figure 12 illustrates a simple example of a driving route from Dallas, TX to Mason, TN without a relay point and with a single relay point. The relay point in this example is located in Arkadelphia, AR.

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Figure 12. An example of a relay point on a driving route

In regard to the With a Relay Point scenario in Figure 12, Arkadelphia, AR serves as a location where truck and trailer equipment could be exchanged. In the Without a Relay Point scenario in Figure 12, the Dallas driver would drive to Mason, and then the driver would need to take a ten hour rest shortly after making the Mason delivery in order to comply with federal hours-of-service rules. The driver would either rest in the truck in the sleeper berth or in a hotel. If the driver rests in the truck, then a sleeper berth truck is required. In the With a Relay Point scenario in Figure 12, the Dallas driver would haul a truckload from Dallas to Arkadelphia and then exchange the truck and trailer with a Mason driver that travels from Mason to Arkadelphia. The drivers would exit Interstate 30 and relay equipment. The Mason driver would take the truckload to Mason for delivery and the Dallas driver would return back to Dallas with the Mason driver’s truck and trailer. By exchanging the equipment at the relay point, the Dallas and Mason driver are back home daily and the drivers can rest at their home instead of sleeping in a truck. Since drivers can rest and sleep at home, day cab trucks are required instead of sleeper cab trucks. Day cab trucks are about $16,000 per unit cheaper than sleeper cab trucks. The Arkadelphia relay point is a physical location established along the highway transportation network off Interstate 30.

If feasible, existing facilities can be used or new facilities must be established at the relay point location. Relay points are determined in-route from origins and final destinations, so costly out-of-route miles are not an issue. The relay point scenario allows the drivers to drive shorter length-of-hauls and to be home daily, whereas, the non-relay point drivers must drive the entire

Without a Relay Point

498 miles

Dallas, TX Mason, TN

With a Relay Point

Relay

Dallas, TX 253 miles Arkadelphia, AR 245 miles Mason, TN

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498 mile length-of-haul and be away from home different days of the week. Similar to the Dallas to Mason path, the mathematical program determines where relay points should be located on a national highway transportation network throughout the U.S. Key costs are included in the mathematical program to appropriately model truck driver, transportation carrier, and customer attributes. Within the MIQP, driver quantity pools are determined and established on the transportation network for each origin-destination path at different relay points. Origins, destinations, and relay points serve as locations where drivers can be domiciled. A domicile is the home base where the drivers live or are stationed. Chapter 5 provides a detailed description of the MIQP and the data used in the program along with the key costs included in the

mathematical program, which reflect the dominant costs for transportation carriers, drivers, and customers.

The relay point scenario generated from the MIQP will be compared to a non-relay point scenario without relay points. Comparisons will be made with regard to cost and performance metrics and driver and equipment quantity requirements. Key cost items focus on driver pay, truck and trailer depreciation, truck and trailer maintenance, and truck and trailer purchase costs.

Performance metrics concentrate on order cycle time, driving length-of-haul, driver home time, driver work hours, driver and truck utilization, and equipment idle time. Purchase costs focus on truck and trailer equipment and the different types of truck equipment required (day cabs or sleeper cabs). Using relay points, drivers can drive day cabs, while most non-relay point drivers require sleeper cabs. A mixture of cost and performance metrics considers the driver,

transportation carrier, and customer together. Derivatives of the total cost, such as, cost per mile, cost per hour, cost per truckload, etc. will be compared between the relay and non-relay point scenarios. Productivity measures will also be included.

In order to study truckload driver transportation and the simultaneous inter-relationships with the transportation carrier and customer, a truckload transportation network is created for modeling purposes. The transportation network is based on actual historical production and

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consumption data and information from the FMM model. Detailed information includes production and consumption truckload volumes throughout the U.S. along with freight distribution truckload volume flows between production and consumption locations, the appropriate transportation mode, and the freight assignment routes between production and consumption locations. Since this study is focused on truck drivers, truck transportation is the only transportation mode considered with specific focus on truckload transportation. To create the transportation network, three phases are executed in the FMM model. The first phase consists of freight generation by establishing the freight production and consumption location points. The second phase involves distributing freight flows between the production and consumption

locations. The third phase consists of creating the appropriate freight route assignments between the freight production and consumption locations. Appendix A outlines, in more detail, the FMM steps involving freight generation, freight distribution, and freight assignment.

51 CHAPTER 5