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Tom O'Rourke, Ph.D.
Geotechnical Engineering

Who Builds Big? | Career Info Index | Engineering Webography

Professor Tom O'Rourke teaches in the School of Civil and Environmental Engineering at Cornell University in Ithaca, New York. His teaching and professional practice has covered many aspects of geotechnical engineering, including earthquake engineering, underground construction, lifeline engineering, foundations, earth-retaining structures, slope stability, and soil/structure interaction.

Check out a project that Tom has worked on: Central Artery/Tunnel Project, Boston, Massachusetts

Tom O'Rourke, Ph.D. Geotechnical Engineering
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What things do you do in geotechnical engineering?
We study and evaluate the ways in which the ground performs. In doing so, we provide stability for your house and office buildings, because all the structures that you use are supported by the ground. We also try to understand how structures that are buried in the ground behave, such as subway systems, water and gas pipelines, and the like. We help design and build the underground space where you might park your car or the underground mall where you may shop. We also evaluate how structures that are made of soil and/or rock behave, such as large earth dams and highway embankments.

What sorts of things do you do in earthquake engineering?
We study the ways in which the ground responds to earthquake shaking. During an earthquake, there can be catastrophic failure of the ground. The ground can literally turn into a liquid by virtue of a phenomenon known as liquefaction. Moreover, landslides occur during earthquakes, and fault ruptures will take place and affect structures built on or across the faults.

Are there particular kinds of structures that you are most likely to study in terms of earthquake impact?
I study the behavior of lifeline systems, which are large networks that provide the resources and services needed to sustain modern communities. They include water supplies, electric power grids, gas and liquid fuel delivery systems, transportation facilities, and wastewater treatment and conveyance networks. The behavior of these systems involves many interesting and complex problems. All are built over large geographic areas and are therefore subject to many different hazards. They comprise many different structures and types of equipment, are fabricated with different materials, and are constructed over many years according to different design practices and levels of workmanship. When an earthquake strikes a lifeline system, there can be a wide variety of responses, all of which affect the ability of the system to provide critical resources, such as water to extinguish fires triggered by the earthquake or electric power for emergency equipment.

I look very closely at the behavior of underground pipeline systems and conduits. These "lifelines" are buried in the ground. So the outcome in terms of survivability and the way in which these systems function are directly tied to the behavior of the ground.

Could any of these systems be described as tunnels?
Absolutely. Tunnels are underground structures that are critical parts of lifeline networks. Tunnels are used for highways, railroads, metros, drinking water conveyance, and the storage and transportation of wastewater. They also can house electric power and telecommunications equipment.

I am currently involved in the seismic design of highway tunnels in Turkey. I provide advice to an international team that is designing and constructing very important tunnels linking Istanbul and Ankara. A severe earthquake that struck Turkey in November 1999 damaged parts of the highway tunnels. A design effort is now under way to create an underground facility that will respond well to the most severe earthquakes that can be expected in the future.

What's the most interesting project you've worked on?
One of them was modeling the water supply of San Francisco. Our engineering research group at Cornell was the first to demonstrate the viability of modern computer graphics and interactive modeling for the earthquake behavior of complex water supplies. This work was supported by the Multidisciplinary Center for Earthquake Engineering Research at the State University of New York. The Center receives support from the National Science Foundation. The Center has made the improvement of lifeline systems one of its key areas of engineering and science development. Our modeling of the San Francisco water supply alerted people; it showed them that the in-ground pipeline system wouldn't function well in a severe earthquake. And as a consequence of our modeling, the Auxiliary Water Supply System, which is used for fire protection in San Francisco, was upgraded. A Portable Water Supply System (PWSS) was developed under the guidance of the then-Assistant Fire Chief, Frank Blackburn, to supplement the in-ground system. The PWSS is composed of large-diameter hosing and special hydrants that are rapidly deployed from the inexhaustible supply of water in San Francisco Bay. It was the PWSS that put out the fire in the San Francisco Marina after the 1989 Loma Prieta earthquake, thereby saving many buildings from burning.

My participation on the Boston Central Artery/Tunnel is very exciting. The Cornell research team was part of the effort managed by the Massachusetts Highway Department and Turnpike Authority and Bechtel Parsons Brinckerhoff to apply a new technology, known as Deep Mixing Methods, at a scale and level of sophistication unprecedented in North America. When the ground is weak and has undesirable characteristics, Deep Mixing Methods can mix cementitious, or cementlike, compounds into the soil to create a more durable, stronger, and stiffer material. That then allows for construction to occur in a much more effective manner. Approximately 800,000 cubic yards of exceptionally weak soils were modified by this deep mixing technology on the Boston Central Artery -- the largest job of its type that's ever been accomplished on this continent.

I participated in the U.S. earthquake reconnaissance mission to Armenia following the 1988 earthquake in that country. The U.S. Reconnaissance Team was asked by the Soviet Academy of Sciences to investigate the aftermath of the earthquake. This reconnaissance occurred during the Cold War, and the capital of Armenia was actually garrisoned with Soviet tanks and troops. The Reconnaissance Team wrote a report summarizing its observations and making recommendations for what could be done to improve the capacity of the Armenian and Soviet infrastructure to sustain a future earthquake.

Last year in October I testified before the U.S. House of Representatives Science Committee on the effects of the devastating 1999 earthquakes in Turkey and Taiwan. I testified on behalf of the Earthquake Engineering Research Institute and the engineering community.

I have also worked recently on very exciting projects for the New York Third Water Tunnel, tunnels to help clean up Massachusetts Bay, rapid transit system in San Juan, Puerto Rico, and a Liquefied Natural Gas facility in Trinidad.

Do you use any special equipment in your work?
Computer-based modeling and experimental modeling at full scale, reduced scale, and small scale through centrifuge tests. The research group at Cornell investigates the materials used to fabricate lifeline systems. We have special testing facilities for soil and rock. We have special testing facilities for polymers that are frequently used to rehabilitate existing structures. The Cornell engineering research group is currently developing special fiber-reinforced polymers that can rehabilitate pipelines to make them more resistant to earthquake and recurrent service loads.

What do you like most about your work?
Diversity. It's always different. And it's always important to people. Whatever we do, if it's water supply, transportation, or energy distribution, it's essential.

What would you describe as the most fun thing about your work?
Creating something that hadn't been there before. And also seeing how people respond to and benefit by it. If you are able to preserve the water supply of San Francisco during an earthquake so that buildings don't burn, that's a significant achievement.

When did you know you wanted to be an engineer?
As I went through my education, I decided that I liked building facilities that people use to improve their lives. That took me into civil and environmental engineering. As a graduate student at the University of Illinois, I conducted research on the Washington, D.C., Metro System. My thesis was focused on the way in which deep excavations in critical urban environments behave. It involved specialized instrumentation and data acquisition on the performance of excavations next to the National Portrait Gallery.

I really enjoyed the work and decided that I wanted to pursue a career in geotechnical engineering. The first area I concentrated on was underground technologies. After coming to Cornell, I started working in earthquake engineering and lifeline systems. Part of my research now involves the advanced use of geographical information systems, and I am privileged to work with some exceptionally talented colleagues in this endeavor.

As a child, were you interested in engineering?
I always was interested in science and did well in science and math in high school. What probably motivated me most were high school counselors who encouraged me to pursue engineering.

What advice would you have for young people who may want to pursue a career in engineering?
I would say that there are plenty of opportunities, and that the demands and needs for good engineering are enormous. Our society has distinguished itself by virtue of its advanced technologies. Scientists discover fundamental characteristics of the physical world that provide opportunities for new technology. Engineers invent and build the facilities and systems that apply the technology in reliable and cost-effective ways.

Our economy and world leadership are increasingly more dependent on the capabilities that we gain from technology. Because engineers are the inventors and implementers of technology, their opportunities are virtually limitless. When deciding what to do, young people should decide to be involved in what they like and derive greatest satisfaction from. People who do what they enjoy are able to derive great satisfaction from life. Moreover, they tend to be successful in their endeavors, and therefore derive economic well-being as well as personal satisfaction from their careers.


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