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Engineering short course targets designs to withstand explosions By Deborah A. Benedetti
Dr. Theodor Krauthammer, professor of civil engineering at Penn State, introduces engineers, architects and safety and security managers from around the world to designing structures to withstand explosions. World Trade Center, New York City: terrorist bomb kills six, 1993 Community Center, Buenos Aires, Argentina: terrorist car bomb kills 99, 1994 Alfred P. Murrah Federal Building, Oklahoma City: terrorist bomb kills 168, 1995 Riyadh, Saudi Arabia: terrorist car bomb kills five Americans, 1995 Khobar Towers, Saudi Arabia: terrorist car bomb kills 19 U.S. service personnel, 1996 Frequent explosive accidents in petrochemical and grain storage facilities	The Cold War may be over, but the world is not a safer place, as the terrorist bombings listed at the top and bottom of this page illustrate. Can buildings be built to either withstand bomb blasts or to minimize such consequences? Dr. Theodor Krauthammer, professor of civil engineering at Penn State, says “Yes.” He teaches an engineering short course titled Modern Protective Structures Design, Analysis and Evaluation, which focuses on designing structures to mitigate the effects of explosions.   “This is probably one of the last frontiers in structural engineering, because we still do not have well-established and fully implemented procedures for designing for the effects of explosive devices,” he said. “We’ve only worked scientifically in this area since the end of World War II. Prior to that, people made decisions about designing and improving structures based on observations of the effects of explosions.”   His course takes a scientific approach to issues of fortification science and technology; analysis, design, assessment and retrofit; industrial explosive safety; antiterrorist design; hazard sources; and physical security. It’s an intensive weeklong program involving lectures, extensive hands-on computer applications and practical in-class and out-of-class exercises. The 1998 short course drew 29 engineers, architects and safety and security managers from civilian and military organizations around the world to Penn State.   Krauthammer, an internationally recognized researcher in enhanced structural performance and safety, has more than 25 years of experience in protective structures and serves as a technical consultant to government and industry in the United States and abroad. His research interests center on structural mechanics and dynamics; earthquake, impact and blast engineering; and experimental, numerical and symbolic methods of analysis. He presented the course in collaboration with Dr. Stanley C. Woodson, research structural engineer at the U.S. Army Corps of Engineers Waterways Experiment Station in Vicksburg, Miss.   “Since the end of the Cold War, one former adversary is in virtual chaos, and other nations are acquiring nuclear weapons technology. During the Cold War, the two powerful adversaries had quite a bit of control over their nuclear weapons and their associates,” Krauthammer said.   Today, ethnic and cultural conflicts and industrial accidents pose threats to both military and civilian populations. The biggest threat involves chemicals and fuels, vapors, combustible dust, explosives (black powder) and high explosives (military-type explosive materials).   Since the 15th century, people have known that two principles protect against blasts: mass and distance, Krauthammer said.   “The heavier the building, the more resistant the building is, and the more separation there is between the explosion and the structure, the less effect the blast has on the building,” he noted.   Civilian buildings generally aren’t built to withstand blasts. They are neither massively constructed nor set far enough back from public access areas to survive conventional explosive devices.   Krauthammer’s goal is to take the scientific research done on the effects of conventional and nuclear weapons during the last 50 years and transition this information for use in the civilian sector. To assist engineers, architects and safety and security managers in designing structures to protect the people inside from the effects of explosive devices, Krauthammer said there are five common-sense questions that must be answered: “Is there going to be an incident? Why? How? When? Where? We need to define the threat of the hazard, define the loads on the structure, make a structural assessment of potential cause-and-effect relationships, and recommend mitigation measures for designing or modifying the structural system.   “We can’t fortify the whole world because something will happen somewhere,” he said. “We have to consider how much safety we want, how much risk we are willing to take and how much we are willing to pay for the desired safety. These are issues that do not have good answers, but as engineers, we still need to provide solutions, even though the underlying problem is not well defined.”   As part of the short course, participants received volumes of printed course notes, appendices and computer manuals, as well as other reference materials. Krauthammer has presented this engineering short course since 1988. The course has been taught at Penn State since 1995.   Penn State’s College of Engineering sponsored the short course, held at The Penn Stater Conference Center Hotel. Outreach and Cooperative Extension’s Conferences and Institutes assisted with planning and delivery. Krauthammer is considering developing more advanced courses and workshops on designing protective structures. An outreach program of the College of Engineering