TxDOT Research Library - TxDOT Research Project

Show:

Evaluate Specialized Hauling Vehicles with Regard to Pavement and Bridge Deterioration and Posting Limit

What Was the Need?

Specialized Hauling Vehicles (SHV) is a modified single-unit truck with 4 to 7 axles. The SHV can be modified by adding 1 to 4 liftable axles that can be raised once the cargo is delivered or, when the SHV is loaded, making steering through an intersection easier, though the potential for overturning might be increased. SHVs may be designed as: dump trucks, construction trucks, ready mix trucks, solid waste trucks and other vehicle types. The Federal Highway Administration (FHWA) requires a state to certify that it does not permit operation of Specialized Hauling Vehicles (SHV) or conducts bridge force effects load rating analyses consistent with the standard American Association of State Highway and Transportation Officials (AASHTO) H820 or HL93 loads and applicable SHV loads based on five configurations (SU4. SU 5, SU6 and SU 7) identified in the AASHTO Manual on Bridge Evaluation. pavement and bridge load rating analyses and will determine load posting requirements. Research was needed to evaluate the deterioration (consumption) rates for pavements and bridges when all axles are on the ground and when axles are lifted to accommodate steering and other operations.

What's the Solution?

This study was performed to ensure that Texas complies with FHWA requirement that each state must conduct bridge force effects load rating analyses before permitting specialized hauling vehicle (SHV). Of 5,693 SU trucks counted, 967 (16.9%) were an SHV of some type. This figure allowed the team to develop representative SHV configurations to quantify SHV deterioration impacts to Texas pavements and bridge. Further, the researchers conducted an analysis of SHV safety performance in terms of crash history and operational characteristics; conducted an economic analysis of SHV operations in Texas; and prepared draft policy regarding SHV operations in Texas to minimize impacts on bridge and pavement load posting needs. The research team also made recommendations regarding bridge load posting signage format for possible inclusion in the TxDOT Manual on Uniform Traffic Control Devices.

Project Number

0-6897

Status

Completed

link icon Copy link to this project.