Feb. 16, 2003

Livermore Engineers Use Computer Simulations to Illustrate Impacts of Bomb Blasts on Infrastructure

DENVER, Colo. — Using advanced computing capabilities, engineers from the Lawrence Livermore National Laboratory will illustrate some of the issues that arise when mitigating the effects of bomb blast on the constructed environment.

Since the attacks on the World Trade Center, the Pentagon and at major U.S. embassies and military facilities abroad, the nation’s bridges, buildings and dams are considered desirable targets for terrorists intent on creating maximum damage and numerous deaths.

Today at the American Association for the Advancement of Science 2003 Annual Meeting in Denver, Colo., Livermore engineers will highlight advanced computer simulations performed at LLNL and the U.S. Army Engineering Research and Development Center. Such simulations can be used to examine the performance of representative structures under blast loadings and explore design alternatives. These regimes of behavior are quite different from those associated with more typical design requirements such as an earthquake.

The simulation technologies employed were originally developed within the Department of Energy’s Defense Programs activities at LLNL and Sandia National Laboratories. Some of these technologies have already found wide acceptance in non-defense uses, such as for crash safety simulation in the automotive industry. Engineer David McCallen of Livermore’s Laser Science Engineering division and colleagues have constructed computer simulations to show what could happen to buildings and dams if someone used conventional explosives. Robert Ferencz of the Laboratory’s Defense Technologies Engineering division represents the group that created the structural dynamics modeling code used in these studies.

"Addressing these technology areas will require research efforts in both component and full-scale experimental testing complemented by computer simulations," McCallen said. "We can now computationally model the complex nonlinear response of structures up to collapse levels."

Ferencz, who will participate in the AAAS session titled "Security for Life: The Science Behind Security Technologies" at 2:30 p.m. MST, noted that blast resistance already is a design criteria for some critical structures. Ferencz and McCallen are interested in how to distribute these capabilities more broadly across our infrastructure. Ferencz will discuss three principal areas:

- The complexity of simulating the interaction of a blast wave with a specific type of structure, which crosscuts both physics and engineering disciplines.

- Development of effective blast resistant designs for new critical structures that may require engineers to think about structural designs in new ways for this unique loading case.

- Development of retrofit methodologies for increasing the blast resistance of existing structures.

Advanced computer simulations can play a key role in homeland security when the understanding gained from combined simulations and field test experiments is used to develop improved blast-resistant design guidance for the broader community of structural engineers.

Founded in 1952, Lawrence Livermore National Laboratory is a national security laboratory, with a mission to ensure national security and apply science and technology to the important issues of our time. Lawrence Livermore National Laboratory is managed by the University of California for the U.S. Department of Energy’s National Nuclear Security Administration.

Laboratory news releases and photos are also available electronically on the World Wide Web of the Internet at URL http://www.llnl.gov/PAO and on UC Newswire.