Experimental investigation of the seismic response of bridge bearings.

Details

• Creators:
  LaFave, James ; Fahnestock, Larry ; Foutch, Douglas ; Steelman, Joshua ; Revell, Jessica ; Filipov, Evgueni ; Hajjar, Jerome
• Corporate Creators:
  Illinois Center for Transportation ; University of Illinois at Urbana-Champaign. Department of Civil and Environmental Engineering
• Corporate Contributors:
  United States. Federal Highway Administration
• Subject/TRT Terms:
  Base Isolation Bridge Bearings Bridge Design Compression Tests Earthquake Resistant Structures Elastomers Highway Bridges Seismicity Shear Properties
• Publication/ Report Number:
  FHWA-ICT-13-002
• Resource Type:
  Tech Report
• Geographical Coverage:
  Illinois
• Corporate Publisher:
  Illinois. Dept. of Transportation. Bureau of Materials and Physical Research
• Abstract:
  The Illinois Department of Transportation (IDOT) commonly uses elastomeric bearings to accommodate thermal
  
  deformations in bridges. These bearings also present an opportunity to achieve a structural response similar to isolation
  
  during seismic events. IDOT has been developing an earthquake resisting system (ERS) to leverage the displacement
  
  capacity available at typical bearings in order to provide seismic protection to substructures of typical bridges. The research
  
  program described in this report was conducted to validate and calibrate IDOT’s current implementation of design practice for
  
  the ERS, based on experiments conducted on typical full-size bearing specimens, as well as computational models capturing
  
  full bridge response. The overall final report is divided into two volumes. This first volume describes the experimental program
  
  and presents results and conclusions obtained from the bearing and retainer tests. The experiments described in this volume
  
  provide data to characterize force-displacement relationships for common bearing types used in Illinois. The testing program
  
  comprised approximately 60 individual tests on some 26 bearing assemblies and components (i.e., retainers). The testing
  
  program included (1) Type I elastomeric bearings, consisting of a steel-reinforced elastomeric block vulcanized to a thick top
  
  plate; (2) Type II elastomeric bearings, distinct from Type I bearings with a steel bottom plate vulcanized to the bottom of the
  
  elastomeric block, and a flat sliding layer with polytetrafluoroethylene (PTFE) and stainless steel mating surfaces between the
  
  elastomer and the superstructure; and (3) low-profile fixed bearings. Tests conducted to simulate transverse bridge motion
  
  also included stiffened L-shaped retainers, consistent with standard IDOT practice. Tests were conducted using monotonic
  
  and cyclic displacement protocols, at compression loads corresponding to a range of elastomer compression stresses from
  
  200 to 800 psi. Peak displacements from initial position ranged from 7-1/2 in. to 12-1/2 in., depending on bearing size. Test
  
  rates were generally quasi-static, but increased velocities up to 4 in./sec were used for bearings with PTFE and for a subset
  
  of other elastomeric bearings. On the basis of all of the experimental findings, bearing fuse force capacities have been
  
  determined, and appropriate shear stiffness and friction coefficient values for seismic response have been characterized and
  
  bracketed.
  
  
• Format:
  PDF
• Funding:
  UILU-ENG-2013-2-12
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:15207616af05969d84875ca620ecaec0deba226a5bfa40ec3d139c07d2a6cf2c3da7c57c5f3d5be3a721b6bf62b1887dfd02f90ca6913c55b87f0dfc94e00c6d
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/27274/dot_27274_DS1.pdf
• File Type:
  [PDF - 4.90 MB ]