Purdue University Study Finds Westinghouse AP1000® Shield Building Is Well Designed to Withstand Strong Earthquakes

PITTSBURGH, June 2, 2011 /PRNewswire/ -- Purdue University researchers have completed large-scale tests to verify the structural integrity of the shield building that contains the main components of the Westinghouse AP1000 nuclear power plant. The researchers determined that the structure is flexible and strong enough to withstand earthquake forces more powerful than federal design requirements, and that the structure provides a significant reserve margin to ensure radiation is contained.    

The study was conducted at Purdue University's Bowen Laboratory, which is internationally recognized for structural testing of large-scale components. This large-scale testing program was led by Dr. Amit H. Varma, Associate Professor of Civil Engineering at Purdue University.  Dr. Varma is a University Faculty Scholar, Director of the Center for Structural Engineering and Emerging Technologies for Nuclear Power Plants, and internationally recognized for his role in current efforts to develop an American Institute of Steel Construction specification for the design of steel-concrete composite structures for safety related nuclear facilities.

The AP1000 shield building design employs an inner steel-wall containment vessel and an outer radiation shield made using a technology called steel-concrete-composite construction. Instead of using more conventional reinforced concrete, which is concrete filled with steel rebars, the steel-concrete approach uses a sandwich of steel faceplates filled with concrete.  

"We conducted a large-scale testing program that included more than twenty full-scale tests on the fundamental out-of-plane behavior, in-plane behavior, anchorage performance, and composite behavior of the steel-concrete composite design used for the shield building," said Dr. Varma. "Some of our test specimens were 40 feet long and 3 feet by 3 feet in cross-sections, requiring the use of our two 30-ton capacity cranes to lift and place in the test setup. The specimens were tested using multiple hydraulic rams capable of exerting 1 million pounds of force each. We had carefully designed and deployed sensors to measure the fundamental behavior and load carrying capacity of the specimens."        

Besides the experimental program, researchers at Purdue University also developed and benchmarked extremely complex state-of-the-art computer models to simulate the measured behavior of the tested specimens. The experimental and computational research complemented each other, and enhanced the robustness and fidelity of the whole effort.

Michael Corletti, Director of New Plant Engineering at Westinghouse said, "The benchmarked models were used to investigate and evaluate the behavior of the steel-composite shield building design subjected to different extreme design and beyond design-basis loading scenarios including aircraft impact, earthquakes, tornado, missile impact, etc."

Dr. Varma added, "Most importantly, the benchmarked computational models were used to demonstrate the performance, overall ductility, and the seismic design philosophy used for the AP1000 shield building design when subjected to safe-shutdown and then beyond design-basis earthquakes."

The large-scale experimental and computational benchmarking research at Purdue was funded by Westinghouse, and the findings will be submitted to the U.S. NRC.  

Purdue University Bowen Laboratory

Purdue University's Bowen Laboratory is an international authority in civil engineering and the research and testing of civil structures. The National Science Foundation announced in 2010 that Purdue will lead a new center, funded with a $105 million NSF grant, called the George E. Brown Jr. Network for Earthquake Engineering Simulation, or NEES.    

Westinghouse Electric Company LLC

With 15,000 employees worldwide, Westinghouse Electric Company LLC, a group company of Toshiba Corporation (TKY:6502), is the world's pioneering nuclear energy company and is a leading supplier of nuclear plant products and technologies to utilities throughout the world.  Westinghouse employs more than 9,000 employees in the U.S., with over 4,000 currently involved in nuclear manufacturing activities through six states.  In 1957, Westinghouse supplied the world's first PWR in the Western Pennsylvania town of Shippingport.  Today, Westinghouse technology is the basis for approximately one-half of the world's operating nuclear plants, including 60 percent of those in the United States and 40 percent worldwide.

SOURCE Westinghouse Electric Company LLC