Representative:

Professor Mircea Grigoriu
Department of Civil and Environmental Engineering
Cornell University
369 Hollister Hall
Ithaca, NY 14853-3501
tel.: 607-255-3334
fax: 607-255-4828
e-mail: mdg12@cornell.edu

Members:

Muawia Barazangi, Rachel Davidson, Mircea Grigoriu, Kenneth C. Hoover, Anthony R. Ingraffea, Philip L.-F. Liu, Thomas D. O’Rourke, Katerina D. Papoulia, William Philpot, Jery R. Stedinger, and Harry E. Stewart

Website(s):

www.cornell.edu

www.engineering.cornell.edu

Cornell research on the seismic response of

Frank H. T. Rhodes Hall houses high-tech facilities of the College of Engineering

structures was initiated in the early 1970s. Emphasis was placed on the behavior of deformed reinforcing bars in concrete structures, lapped splices in beams, columns, and flat elements, and dowel action in reinforced concrete subjected to severe reversing loads. This research, which featured numerous innovative experimental programs, led to greatly improved understanding of behavior degradation from earthquake effects and to improved design provisions. Extensive experimental and analytical studies were performed of the response of reinforced concrete secondary containment structures (for nuclear power plants) to seismic loadings. Large-scale experiments on reinforced concrete panels under combined biaxial tension and reversing in-plane shear forces were a central component of the work.

Cornell research has been active in the area of Lifeline Earthquake Engineering that focuses on the seismic performance of geographically dispersed systems, including electric power, gas and liquid fuel, telecommunication, transportation, wastewater conveyance, and water supply systems. Research contributions include the characterization and modeling of earthquake-induced permanent and transient ground movement on underground structures, such as pipelines, conduits, and tunnels. Cornell researchers were the first to develop programs and analytical methods to assess the seismic response of water supply networks. Probabilistic hydraulic network models were developed for the Auxiliary Water Supply System of San Francisco and calibrated with respect to the effects of the 1989 Loma Prieta Earthquake.

Cornell research has also focused on advanced geographical information system (GIS) characterization of water supplies, regional seismic hazards, and earthquake effects on water transmission and distribution systems. Research on the seismic response of water supply networks was undertaken with the Los Angeles Department of Water and Power and has involved the application of fiber reinforced composites for seismic strengthening of critical trunk pipelines.

Research in the geotechnical area has been exceptionally active, with work concentrated on soil liquefaction, local site response, pipeline component and system performance in response to ground failure, and the effects of earthquake-induced lateral spread on deep foundations. Cornell researchers have developed analytical models and computer codes for evaluating pile and pipeline response to permanent ground deformation triggered by earthquakes.

Learning from Earthquakes

Cornell researchers have been active in documenting the effects of earthquakes through reconnaissance performed immediately after major seismic events. Members of the faculty have played key roles in reconnaissance missions for the 1987 Ecuador, 1988 Armenia, 1989 Loma Prieta, 1994 Northridge, 1995 Kobe, 1999 Kocaeli, and 1999 Chi-chi earthquakes. In many instances, these missions have resulted in sponsored research and reconstruction projects in the earthquake-affected areas.

Earthquake Engineering Research Centers

Cornell has been a principal partnering institution in the National Center for Earthquake Engineering Research, NCEER, (1986-1997) and the Multidisciplinary Center for Earthquake Engineering Research, MCEER, (1997-present). Cornell faculty members have been members of the Executive and Research Committees of these Centers since their inceptions.

Network for Earthquake Engineering Simulation (NEES)

In 2002, Cornell received a NSF NEES award to significantly upgrade geotechnical and lifeline engineering experimental facilities

Courses related to earthquake engineering are taught by the School of Civil and Environmental Engineering and the Department of Earth and Atmospheric Sciences. They include courses on structural dynamics, soil dynamics, earthquakes, and seismology. Seminars on earthquake engineering topics are held regularly. An endowed seminar, the Peter Gergely Seminar Series, provides the opportunity to invite internationally renowned earthquake engineering experts to lecture at Cornell.

Cornell has a very active Student Chapter of the Earthquake Engineering Research Institute. Several seminars are sponsored by this student organization every year. The Outstanding Student Paper Award, given yearly by the Earthquake Engineering Research Institute, has been won twice in the last decade by Cornell students.

Master of Engineering [ME(C)] in Civil Engineering is a one-year master’s degree program for baccalaureate engineers who plan to enter engineering practice or management. Cornell ME (C) students undergo intensive, rigorous coursework and involvement in a two-semester project. The project involves a major real-world problem presented by design and management professionals.

Master of Science (M.S.) and Doctor of Philosophy (Ph.D.) in Civil Engineering programs require each student to plan an individualized course of study with the assistance of a special committee made up of faculty members representing major and minor areas of study. The typical M.S. program takes one and one-half to two years to complete, and the Ph.D. degree usually requires at least two additional years. Both degrees require a thesis and a final oral examination; the Ph.D. also involves qualifying and comprehensive examinations.

The George Winter Laboratory includes roughly 10,000 ft2 of laboratory space. There is a crane bay 55 ft. x 60 ft. (3,300 ft2) by 40 ft. high, a 5,500 ft2 low bay and a 2,000 ft2 Concrete Materials Laboratory. The crane bay and low bay provide space for implementing a wide variety of structural and geotechnical engineering research projects for the Civil Infrastructure group at Cornell.

The Crane Bay comprises approximately 3,300 ft2 of floor space. It has 18 ft. high, 12 in. thick concrete walls spanning the 15 ft. horizontal distances between heavy, laced, concrete jacketed columns that support the roof. A 10-ton capacity crane services the bay. A 2-ton capacity forklift (with a 14 ft. lifting height) services the Winter and Concrete Labs. Several large testing facilities exist in the crane bay. The bay contains an earthquake simulator that measures 5 ft. by 7 ft. It is used to simulate earthquake effects on small-scale models and for educational purposes.

The connected Low Bay is 17 ft. high. It houses a 400-kip Baldwin Universal Testing Machine that is set up to test reinforced concrete beams, various types of pipelines and pipeline components, and fiber reinforced composite materials. Many other testing machines, including uniaxial testing devices, are deployed in this sector of the lab.

The Concrete Materials Lab is a 2044 ft2 space with a 17 ft. ceiling attached to the low bay of the George Winter Lab. It provides space and houses equipment for concrete materials research.

Instrumentation - A variety of high resolution, multi-channel, IEEE488 measuring systems are available for use throughout the testing labs (for measuring as many as 220 channels during experiments). Another group of data acquisition systems, based on personal computers with high speed data acquisition cards, allows measurements of as many as 192 channels during dynamic tests. These systems can be used separately for smaller research projects or in combination for larger projects.

The Takeo Mogami Geotechnical Laboratory has excellent facilities for experimental testing, particularly with respect to soil dynamics. The laboratory comprises 2,205 ft2 of usable space. The laboratory is equipped with a walk-in environmental room, with a temperature range of -20 to 60&Mac251; C. Monitoring systems allow for temperature control within ± 0.5&Mac251; C, with additional controls for programmed temperature sequences.

Special testing equipment includes a variety of systems for cyclic and dynamic soil testing. One system is a resonant column/torsional shear (RC/TS) system. This device can test solid or hollow cylindrical specimens in either static or cyclic operation, using either stress- or strain-controlled load steps. The RC oscillator can be operated independently of the TS drive mechanism, allowing dynamic stiffness to be measured at any static strain level.

An NGI-type direct simple shear (DSS) system is driven by a servo-hydraulic cylinder, and is used with circular specimens, approximately 20 mm high, with cross-sectional areas or either 35 or 50 cm2. Test controls for the DSS device and a separate two-post vertical load frame are provided by two servo-hydraulic controllers, each having a wide range of capabilities.

Field Testing Capabilities - A key aspect of geotechnical engineering research at Cornell is field experiments. A large percentage of research projects have included a substantial component of full-scale field verification tests. These tests have included measuring foundation capacities, the responses of cast iron gas mains subjected to both parallel and perpendicular excavations, special testing of high-pressure gas pipelines, and blast and vibration monitoring. The projects rely extensively upon an understanding of operating practices typical throughout the construction and utility industries, as well as the use of sophisticated instrumentation and data acquisition techniques. A special high-speed acquisition system is used for many of these projects, which is capable of collecting data at 100 kHz. These high acquisition rates are necessary for capturing dynamic measurements and when working with soil-structure problems that require a large number of instruments to be read simultaneously.