DESIGNING ORDINARY BRIDGES FOR GROUND FAULT RUPTURE

Ground fault rupture from past seismic events, both vertical and horizontal, was discovered by site trenching during the final design phase of an otherwise ordinary freeway completion project in San Bernardino, California. Several existing and proposed new bridges of various span lengths and column height configurations are in the area of the fault rupture and it was not feasible to avoid the entire fault zone by revising the roadway alignments. With no established criteria or precedent for considering ground fault rupture at ordinary bridges, special design approaches were necessary. A determination of fault rupture magnitude for design or evaluation of structures was made using both deterministic and probabilistic methods. Concept studies were performed to determine whether or not it was feasible to use the California Department of Transportation (Caltrans) normally preferred continuous span monolithic frame structure configuration for the new bridges. There was also the question of whether to design for fault rupture as a separate loading condition or in combination with the severe near fault ground shaking applicable at this site, and if so how to do this. A special technical advisory panel was used by Caltrans to provide additional guidance on both the seismic and structural issues. The resulting design method provides a reasonable measure of confidence regarding collapse prevention from possible future seismic ground rupture permanent displacement, and accomplishes this without a highly complex bridge design procedure.

• 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
• Authors:
  • Gloyd, S
  • Fares, R
  • Sanchez, A
  • Trinh, V
• Conference:
  • Third National Seismic Conference and Workshop on Bridges and Highways: Advances in Engineering and Technology for the Seismic Safety of Bridges in the New Millennium
  • Location: Portland, Oregon
  • Date: 2002-4-28 to 2002-5-1
• Publication Date: 2002-3-11

Language

• English

Media Info

• Features: Figures; Photos; References; Tables;
• Pagination: p. 149-161

Subject/Index Terms

• TRT Terms: Bridge design; Collapse; Earthquake resistant design; Faults; Prevention; Rupture surfaces; Seismicity
• Geographic Terms: San Bernardino (California)
• Subject Areas: Bridges and other structures; Design; Highways; Security and Emergencies; I24: Design of Bridges and Retaining Walls;

Filing Info

• Accession Number: 00933590
• Record Type: Publication
• Files: TRIS
• Created Date: Nov 1 2002 12:00AM