by Lauren Bringle/Wireless Networking & Communications Group, Center for Transportation Research at The University of Texas at Austin
With an increasing demand for Texas products around the world, a growing economy and NAFTA, freight increases need to occur. As freight tonnage increases, heavier trucks are needed that can more efficiently transport freight from place to place. However, increased truck weight also means accelerated pavement and bridge decay that must be addressed.
Born from a partnership between the TxDOT State Legislative Affairs (SLA) section and subject matter experts, as well as Center for Transportation Research (CTR) at The University of Texas Austin and researchers from The University of Texas at San Antonio (UTSA), this research team is revolutionizing how lawmakers make decisions about freight. Researchers on the team include CTR’s Drs. Michael Murphy and Jorge Prozzi, as well as UTSA’s Drs. Jose Weissmann and Angela Weissmann.
Through the development of new tools, resources and conversations with government bodies and truck industry experts, the research team has already helped rewrite legislation to improve safety and reduce the physical toll of large trucks on existing infrastructure while still meeting the cargo load increases desired by trucking companies and their customers.
“The Senate bills originally introduced in 2015 would have had a much greater impact on pavement and bridge consumption due to lack of clear language in the bills to specify the axle, axle group and gross vehicle weight load limits, the spacing between axles and the permit fee rate compared to the infrastructure consumption rate,” Murphy states.
Thanks to their research however, the new bills, which will become law in September, contain language that help keep roadways nicer longer, with less money needed for upkeep, as well as continue to increase demands for higher cargo loads.
To make data such as this more accessible to policy-makers, the CTR team created the State Legislative Affairs Truck Configuration Library
The Library, which stores and manages data and findings concerning truck types, sizes and configurations, dimensions, load distribution, infrastructure management, safety and the effect of freight transport on pavement and bridges, helps inform lawmakers in charge of transportation policies. The database also provides information on pavement and bridge consumption costs, meaning data regarding the wear and tear caused by cargo trucks on the road system, and safety information such as load ratings for various road corridors and bridges that could not handle heavier configurations.
By combining this data into a single spot, the Library has a considerable role to play in today’s order everything shipped to your doorstep world.
The SLA contracted CTR in early 2016 to develop this detailed database so that SLA and their subject matter experts would be better equipped to answer legislative questions whenever they arise. Essentially, the Library saves time and enables better informed policy-making since the database provides insights into the impacts of proposed changes to truck size and weight during the legislative session.
Before this database, no standardized method existed for finding this information, and research initiated during the legislative session often took too long to complete before the session ended.
To update the information in this database and gain insight into weights and configurations for the 2017 legislative session, CTR and collaborators led two workshops with trucking industry and conducted interviews with the Texas Department of Motor Vehicles, Motor Carrier Division, Vehicle Titles and Registration Division and the Texas Department of Public Safety.
CTR’s Murphy presented container chassis and container size combinations to these government and industry partners to illustrate the various possibilities for how to configure freight.
“We worked to prepare analyses that directly impacted Senate bill language relating to oversize and overweight truck legislation,” Murphy states. “Two Senate bills were passed with significant revisions to allowable axle, axle group and axle spacing for milk tanker trucks and sealed ocean containers.”
In addition to these achievements, Murphy adds, the information concerning pavement and bridge consumption rates the researchers provided to legislators also helps them determine permit fees for overweight and oversized trucks. Since accelerated bridge and pavement consumption also means increased revenue needed for repairs, permit fees are important since they can help partially recuperate these increased costs of operation.
According to Murphy, the goal of these discussions with industry is to understand how changes in operation could affect load distribution and a truck driver’s ability to adjust load among axles and axle groups. For the 2017 session, the research team used a program known as Load Xpert and the resulting information to observe commonly used truck configurations, as well as hypothetical alternatives for future planning.
Load Xpert is a truck modeling and load calculation analysis software that allows users to create diagrams and visually configure most types of trucks. With the click of a button, loads can be added and removed, dimensions can be changed and the program will automatically adjust axle loads and weight distribution. The program works in partnership with the Federal Bridge Formula, which instantly assesses potential loads and vehicles for road compliance.
Using Load Xpert along with collecting new data, the CTR team updated the configuration library based on three truck operational types. These included ready mix trucks, milk tank trucks and ocean containers. The team also included a truck that demonstrates the maximum legal size and weight permitted in Texas and a complete Load Xpert analysis, along with variables that compare for higher and lower consumption.
“We also did extensive analysis of multi-axle ready-mix trucks and showed that some of the configurations included in the 2015 legislation could not be legally operated at the axle load limits requested,” Murphy states. “Based on our analyses performed through Load Xpert and presentations to the trucking and ready-mix industries, the industries decided to withdraw their requests for increased weight limits until further evaluations of their needs could be made.”
With freight demands, road pavement and bridge technology constantly evolving, Murphy and his colleagues’ work is far from over. But by providing adaptable tools and resources for the public, they help pave a path to improving freight transport for generations to come.