Engineers receive $817,000 to create university facility
to better understand response of building materials to fire
September 9, 2005
AUSTIN, Texas—Civil and mechanical engineers at The University of Texas at Austin have received an $817,000 grant to create the first university center to study the impact of fire on the integrity of building components.
Dr. Karl Frank, director of the Phil M. Ferguson Structural Engineering Lab that received the National Science Foundation grant, said the Sept. 11, 2001, collapse of buildings at the World Trade Center (WTC) was a wake-up call for American structural engineers to focus more attention on high-temperature scenarios.
“The World Trade Center catastrophe stunned the world, and it shocked structural engineers,” said Frank, holder of the Warren S. Bellows Centennial Professorship in Civil Engineering. “We didn’t expect those buildings to fall.”
The impact of the hijacked planes that hit the WTC started a chain of events that ultimately led steel columns in the core of the two buildings and joists supporting their floors to lose their strength as the temperature of the members increased from raging fires. The columns and joists carried the weight of each floor. Once these elements gave way, the weight of a falling floor overloaded those beneath it, causing a domino-like failure.
With the grant, Frank and others at the J.J. Pickle Research Center lab will test how steel and other materials respond to increasingly high temperatures. Specimens will be placed in digitally controlled test frames that can apply loads to the material while the material undergoes heating that can occur in a fire. One test frame purchased with grant funds can apply a maximum of 22,000 pounds of force on a test material; the other, with a 20-foot height, up to 550,000 pounds of force.
Each test frame will be outfitted with digitally controlled furnaces which Frank is purchasing, creating enclosed heating chambers. The furnaces will heat material up to 2,000 degrees Fahrenheit, or twice the temperature that is usually considered failure in standard fire tests.
“We will test a variety of materials at different temperatures so we can determine the loss of their strength as the temperature goes up,” Frank said.
Wooden trusses, concrete connections and new materials will be studied as well as steel. New materials include fiber-reinforced plastics, which are being used to strengthen and repair connections between beams and columns that support the loads in concrete structures.
Traditional building steel, favored for its strength at room temperatures, is easier to weaken than other materials like wood at high temperatures. Frank and colleagues will test the heat response of steel alloys that have chemicals added to enhance the steel’s strength at high temperatures. They will also test connection details such as steel connections with high-strength bolts, wood trusses connected with steel plates, and reinforced concrete connections.
Civil engineering faculty besides Frank who will perform heating studies using the new equipment are: Professor Michael D. Englehardt, Professor Sharon Wood, Associate Professor Dan L. Wheat and Assistant Professor Oguzhan Bayrack. In the Department of Mechanical Engineering, participants are Associate Professors Ofodike Ezekoye and Eric Taleff. The experiments will also be videotaped and shared with students in the College of Engineering.
“The behavior of building materials in fire, and how rapidly some materials deteriorate, is something most engineers don’t have a conceptual understanding of,” Frank said.