Assessment of Stress Conditions of the Retrofitted Chi-Lu Cable-Stayed Bridge

Chi-Lu main bridge, a single-pylon symmetrical cable-stayed bridge with two equal spans of 120m each, was suddenly and seriously devastated by a strong earthquake of a magnitude of 7.3 on the Richter scale, that occurred about 3 kilometers north of the bridge in Chi-Chi during September 1999. The bridge was almost complete. For safety concerns, urgent repair to the damaged structural components of the bridge, except its cable system, was undertaken without having made a detailed analysis of the structure following the earthquake. As the stress conditions of the bridge structure became unknown after the urgent repair, it became an important issue to evaluate the stress conditions of the bridge in various stages because the bridge was ready to be opened for traffic during the retrofit stage as well as the eventual long-term service stage. In order to verify the allowable live-load capacity of the bridge, heavy trucks were loaded on the bridge deck for testing. Right before the official opening, the natural frequency of the retrofitted structure was also determined by using the ambient vibration and the forced vibration methods. For an evaluation of the overall structural safety of the retrofitted Chi-Lu Cable-stayed Bridge, it was necessary to assess the stress conditions of the structural system after it was repaired. To statically determine the stress conditions of the bridge, inherent statistical indeterminacy was purged from the original structural system by replacing all stay cables and the two side piers with a set of external forces. The bridge began its construction in 1996 and was severely damaged in 1999 and officially opened for traffic in 2004. The purpose of this paper is to present the methods used to evaluate or assess the stress conditions of the bridge during its various stages.

• Corporate Authors:

  Multidisciplinary Center for Earthquake Engineering Research

  State University of New York, 107 Red Jacket Quadrangle, P.O. Box 610025
  Buffalo, NY  United States  14261-0025

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Chen, C C
  • Chang, Kuo Chun
  • Lee, Z K
• Conference:
  • Fourth International Workshop on Seismic Design and Retrofit of Transportation Facilities
  • Location: San Francisco CA, United States
  • Date: 2006-3-13 to 2006-3-14
• Publication Date: 2006-4-3

Language

• English

Media Info

• Media Type: Print
• Features: Figures; References;
• Pagination: 6p
• Monograph Title: Proceedings of the Fourth International Workshop on Seismic Design and Retrofit of Transportation Facilities

Subject/Index Terms

• TRT Terms: Bridge design; Cable stayed bridges; Deformation curve; Earthquake resistant design; Earthquake resistant structures; Live loads; Retrofitting; Seismicity; Service life; Strain measurement
• Identifier Terms: Chi-Lu Bridge (Taiwan)
• Subject Areas: Bridges and other structures; Design; Highways; I24: Design of Bridges and Retaining Walls;

Filing Info

• Accession Number: 01079353
• Record Type: Publication
• Files: TRIS, USDOT
• Created Date: Oct 22 2007 10:14AM