The concern over bridge vulnerability in the United States has grown at an accelerated rate over the past 10 years. The cause is not only accumulated wear and tear on infrastructure but also the rise in domestic and international terrorist activities.
This has led to significant interest in bridge-specific protective design, particularly in the multifaceted area of blast-resistance. And here at the Cockrell School of Engineering, one graduate student decided to hone in on just that.
Eric Sammarco, a doctoral candidate and graduate research assistant who came to The University of Texas at Austin in 2009, studies blast-resistant analysis and design in the Department of Civil, Architectural and Environmental Engineering. Sammarco’s research focuses on the development of vulnerability-assessment software for blast-loaded bridge components.
“What drew me to this project was that it showed strong, practical value,” he said.
The protection of the nation’s highway bridges has been identified as a national security issue. As a result, organizations such as the National Cooperative Highway Research Program (NCHRP) are cultivating bridge-specific protective design provisions and engineering tools to implement into practice.
Sammarco and his team’s software is one such example. Using data from experimental and computational research, the software can determine vulnerability of existing bridges as well as help guide new bridge design. The proposed software, called Anti-Terrorist Planner for Bridges (ATP-Bridge), characterizes blast loads on critical bridge elements, predicts dynamic response and provides an estimate of incurred damage.
An ATP-Bridge user defines a bridge component of interest, including geometry, dimensions, construction material and boundary conditions, and postulates a threat scenario. The current version of the software is able to consider bulk explosive detonations as well as various man-portable threats. With regard to critical bridge components, the software currently addresses reinforced concrete bridge columns, steel suspension bridge tower panels, reinforced concrete bridge tower panels and high-strength steel cable components.
“This area of research is of great interest to me because it offers complex engineering challenges, is a relatively new ‘public domain’ field of study and has the potential to positively impact the entire nation,” Sammarco said.
Sammarco and his research team develop ATP-Bridge under the supervision of professor Eric Williamson, who serves as the principal investigator on the project. In 2010, Williamson and professor Oguzhan Bayrak developed the first-ever national guidelines for designing reinforced concrete bridge columns to better withstand blast loads (NCHRP Report 645).
“I consider myself extremely fortunate to have the opportunity to work on this challenging and rewarding project with professor Williamson and the research team,” Sammarco said. “It has enabled me to grow exponentially, both professionally and personally, over the past four years.”
ATP-Bridge has been validated using experimental test results gathered from various sources such as the NCHRP and the U.S. Army Engineer Research and Development Center. The U.S. military has already utilized a preliminary version of the software in a wartime theater situation. It will be owned and maintained by the U.S. Army Corps of Engineers and will soon be available for distribution to government agencies and qualified government contractors.
“[ATP-Bridge] has been well-received by the sponsor and other government agencies, and the engineering community has been very receptive to the research topic,” Sammarco said. “The idea behind the software is for it to be continually updated and enhanced as new test data becomes available.”
ATP-Bridge is intended to facilitate rapid in-situ vulnerability assessments and anti-terrorist/force protection retrofits of existing bridges and safer designs of new bridges.
The project team recently demonstrated the software in New York City for state transportation engineers and the New York Port Authority, which resulted in invitations to hold additional workshops in other states.
Sammarco, who was featured in the January issue of Structural Engineer, is a registered Professional Engineer in the state of Texas. He plans to finish his dissertation and graduate this year. Upon graduation, he will join San Diego-based structural engineering firm Tobolski Watkins Engineering, Inc., with a main objective to develop a regional office in Austin.
“This is my ideal job,” Sammarco said, “one in which I get to work on challenging and practical problems while also maintaining an involvement with applied research and technology development.”
A more in-depth version of this story appears on the Department of Civil, Architectural and Environmental Engineering’s website.
Eric Sammarco may be contacted at
