Major transportation structures, such as bridges, have suffered tremendous damage in recent earthquakes, including the 1989 Loma Prieta, 1994 Northridge, 1995 Hyogo-Ken Nanbu, 1999 Turkey, 1999 Taiwan and 2001 Nisqually earthquakes. Such damage limits the ability of the affected community to carry out emergency response operations, slows recovery, and strains the limited resources available for post-event reconstruction and development. The current seismic design procedure for bridge columns in the U.S. are based on theoretical and computational models that are calibrated against experimental data. Nearly all of these data are from tests on reduced-scale specimens. Many critical behavior modes, such as shear and cracking of concrete, bond between reinforcing steel and concrete, and local buckling and fatigue-related rupture of steel rebars are known to be sensitive to scale.( i.e. scale effects.) Quasi-static and pseudo-dynamic tests, and reduced-scale shaking table tests, alter strain rates, which can also affect dynamic behavior. Innovative technologies, such as seismic isolation and supplemental energy dissipation systems, have properties that can be sensitive to scale and rate. The lack of shaking table data on full-scale benchmark specimens that validate our understanding of the highly non-linear, multi-axial performance of full-scale bridge columns subjected to input motions representative of large earthquakes, has led many researchers, bridge engineers and practitioners to call for the validation of current experimental testing, design and analysis methods. In 2007 and 2008, through the international cooperation between U.S. National Science Foundation (Network Earthquake Engineering Simulation NEES program) and Japan National Research Institute of Earth Science and Disaster Prevention (NIED), a series of full-scale bridge column tests will be tested according to Japanese design practices using the new E-Defense earthquake simulator in Miki-city, Japan (the world largest shaking table (15Meters X 20Meters with 1,200Ton capacity). Results will provide critical evidence regarding the safety and performance that can be achieved by current Japanese design practice in bridges. While these tests will be of general interest worldwide, they do not by themselves address specific U.S. design and seismic safety concerns due to the significant differences between the U.S. and Japanese design methods. However, by cooperating with NSF (U.S.) and NIED¿s (Japan) E-Defense program, and co-funding with NSF a full-scale testing program of a column designed to U.S. standards, an exceptional near-term opportunity exists to address the concerns of many U.S. practitioners and researchers.

The objective of this pooled-fund study is to provide a benchmark of the seismic performance testing of the U.S. highway bridge column under full-scale shake-table tests. The test results from this study will be used to evaluate and calibrate current design and analysis practices; and will be compared with previous scaled model tests to understand the scale effects.

Task 1: Organize an oversight committee to advise and promote the overall study. Task 2: Develop a detailed work plan to conduct this study with the oversight committee. Task 3: Design a baseline cantilever column to current seismic design criteria for a highly seismic site. Task 4: Design an isolation system and a supplemental energy dissipation system for the bridge. Task 5: Fabricate and construct full scale bridge column(s) Task 6: Conduct the full-scale shake-table experiments in cooperation with NSF and NIED. Task 7: Carry out post-test numerical simulations and other studies of the US tests and Japanese full-scale column tests to assess a) the effects of scale and strain rate, including adequacy of reduced scale models; b) adequacy of the current numerical models and modeling parameters as used in design practice and research; c) observed performance in comparison with performance objectives; d) relative behavior of the US and Japanese designs; and e) effectiveness of seismic isolation and energy dissipation systems. Task 8: Report findings and recommendations.

Currently, NSF has committed and provided research funds of $200K; and FHWA along with the recipients (Univ. of Nevada at Reno and University of Buffalo) of the FHWA seismic research program contracts have committed $200K. Caltrans and other interested State DOTs are solicited to participate.