Department of Civil Engineering
College of Engineering
NMSU Bridge Inspection Program
(September 29, 2014) The nation’s aging infrastructure may not be a concern for most until an accident happens, but faculty, staff and students in the New Mexico State University Bridge Inspection Program are working to prevent tragedies and keep citizens safe. NMSU’s Bridge Inspection Program, which is in the Civil Engineering Department of the College of Engineering, handles a large number of inspections for the New Mexico Department of Transportation. David Jauregui, NMSU’s Wells-Hatch Professor of Civil Engineering, directs the program. He was honored at NMSU’s Scholarly Excellence Rally Friday, Sept. 26.
“The NMSU Bridge Inspection Program strives to educate students in the five elements of bridge engineering and that includes the design, construction, inspection, evaluation and maintenance of bridges. The bridge program incorporates students into that whole cycle,” Jauregui said. Co-op undergraduate students in the NMSU College of Engineering perform on-site bridge inspections and are supervised by professional engineers. Graduate students, focusing in structural engineering, conduct load capacity ratings. Both the bridge inspections and ratings are conducted in accordance with professional standards distributed by the NMDOT, the Federal Highway Administration and the American Association of State Highway and Transportation Officials.
A current issue in New Mexico is the lack of bridge design documentation. One of the program’s projects is to create a procedure for load rating bridges that do not have plans on file. The team is responsible for evaluating bridges without plans, which starts with the engineers conducting a visual inspection of the bridge. They examine the deck, superstructure, substructure, channel and channel protection.
Students examine many different types of bridges such as steel, reinforced concrete, prestressed concrete and timber. Students assess everything related to the safety of the bridges including the surrounding components such as the approach roadway, waterway underneath the structure and guardrails. The quality of the concrete and steel along with material durability used to construct the bridges are critical factors that determine the longevity of the bridges. When the country’s interstate system was designed in the 1950s, the average lifespan of a bridge was 50 years. Newly constructed bridges have an expected lifespan of 75-100 years.
Increased load levels traveling over bridges are one of the major issues with the structures. With heavy traffic from commercial trucks, loads that exceed the designed limit can cause bridge components to become overstressed and crack, buckle or crush. “The major goal of the NMSU Bridge Inspection Program is to ensure that highway bridges continue to provide safety and serviceability to the traveling public,” Jauregui said. “The documentation that we provide to the NMDOT is used to make decisions related to future maintenance, rehabilitation, retrofit or replacement of structures.”
Undergraduate students travel throughout the state and inspect approximately 150 bridges as part of a six-month co-op assignment. “The beauty of the program is that once they finish this six-month appointment they are given other opportunities through the NMSU Department of Civil Engineering to pursue applied research related to capacity evaluation of structures, which directly ties into the inspection,” he said. “We are investigating and developing analytical and experimental techniques to determine the load capacity of New Mexico bridges, in particular those without design plans, and other states have expressed interest in adopting our procedures.”
Jauregui directs a team that includes eight undergraduate students, 10 graduate students and two NMSU colleagues, Craig Newtson and Brad Weldon. According to Jauregui, the engineering skills students are learning are not limited to bridges; they also are learning about forensic engineering. “The basic way we would inspect any type of structure that experiences some type of damage following an event, such as an overload, earthquake, flood or wind, can be related to bridge inspection so students have the experience to apply their expertise to the evaluation of buildings, monuments, those types of structures,” he said.
“Students come out of the program with a very special set of skills that is not available anywhere else in the U.S.,” Jauregui said. “I feel very proud to be the director of this program and appreciative of the collaboration we have with the NMDOT in bridge-related projects and contributing to the safe travel of the public here in New Mexico.”
-Article by Tiffany Acosta, photo by Darrell Pehr. See more at newscenter.nmsu.edu.
Program funded by grants from the New Mexico Department of Transportation and from many other entities.