Category: Completed Projects
Group: Seismic
Subject: Self Centering Bent
State: Washington Abstract: In this study the post-earthquake residual displacements of reinforced concrete bridge bents were investigated. The system had mild steel that was intended to dissipate energy and an unbonded, post-tensioned tendon that was supposed to remain elastic and re-center the column. The columns tested had different mild steel to prestress ratios, which affected their re-centering ability. A re- centering ratio developed by Hieber (2005), which took into account the external axial load, initial prestress force, and the mild steel ratio, was used to predict these re-centering capabilities.
Budget (USD): 0.00
Project length: 0
Project Starting Year: 2008
Project Completion Year: 2008
View UW_WARD_684_3_DRAFT_Concrete_Bridge_Bent.pdf
Go to: http://www.wsdot.wa.gov/eesc/bridge/abc/UW_WARD_684_3_DRAFT_Concrete_Bridge_Bent.pdf
Group: Seismic
Subject: Self Centering Bent
State: Washington Abstract: In this study the post-earthquake residual displacements of reinforced concrete bridge bents were investigated. The system had mild steel that was intended to dissipate energy and an unbonded, post-tensioned tendon that was supposed to remain elastic and re-center the column. The columns tested had different mild steel to prestress ratios, which affected their re-centering ability. A re- centering ratio developed by Hieber (2005), which took into account the external axial load, initial prestress force, and the mild steel ratio, was used to predict these re-centering capabilities.
Two 40 percent scale specimens with large-bar connection details and a central unbonded, post- tensioned tendon were tested by using pseudo-static loading. The large-bar system is a rapidly constructible precast system for use in seismic regions. The test columns had re-centering ratios of 1.6 and 1.2. A column with the same connection details but no prestress and a re-centering ratio of 0.9 was used as a reference. The displacement at zero force in the test was used as a proxy for the residual displacement after an earthquake.
The tests showed that columns with a larger re-centering ratio did experience lower residual drifts, although this distinction only became clear for drift ratios that exceeded 2 percent. The tests also showed that increases in post-tensioning force led to slight increases in damage at high drift ratios.
Key Words: Posttensioning, precast concrete, bridge substructure, columns, residual displacement, residual drift
Specific ABC aspect:
Budget and Timeline
Budget (USD): 0.00
Project length: 0
Project Starting Year: 2008
Project Completion Year: 2008
Primary Sponsor
Washington State Department of Transportation
Research Office Transportation Building, MS 47370
Olympia, WA 98504 USA
Kim Willoughby
360-705-7978
U.S. Department of Transportation
Office of the Secretary of Transp.
400 7th St. SW
Washington, DC 20590 USA
Primary Performing Organization
Washington State Transportation Center (TRAC)
University of Washington, Box 354802
University District Building;
1107 NE 45th Street, Suite 535
Seattle, WA 98105-4631 USA
PI: Mark Eberhard, Professor
Co-PI: John Stanton, Professor
Other Documents
View UW_WARD_684_3_DRAFT_Concrete_Bridge_Bent.pdf
Other Related URLs
Go to: http://www.wsdot.wa.gov/eesc/bridge/abc/UW_WARD_684_3_DRAFT_Concrete_Bridge_Bent.pdf
