Enhancement of National LRFD Codes for California Bridge Design: Hinge Curl Research

This task is intended to provide resources needed to research multi-frame prestressed box girder structures that require hinges to allow expansion and contraction due to thermal effects. The construction of these hinges is complicated by the fact that prestressing causes time dependent deformation. In particular, the short cantilever side of the hinge tends to "curl" upward due to the effect of prestressing. This curl continues until load transfer is completed from the suspended side of the hinge (usually after false work is removed). This makes it difficult to set screed line elevations since it depends on the amount of curl as well as the time until load transfer. This issue has been addressed in Memo to Designers (MTD) 11-34. However, the equations and methodology used in this memo are unproven and easily misinterpreted. A proposed revision to this memo is recommended (and will be attached to the proposal).

Language

• English

Project

• Status: Active
• Sponsor Organizations:

  California Department of Transportation

  1227 O Street
  Sacramento, CA  United States  95843
• Project Managers:

  Sah, Kamal

• Performing Organizations:

  University of Nevada, Reno

  College of Engineering
  Reno, NV  United States  89557
• Start Date: 20100630
• Expected Completion Date: 0
• Actual Completion Date: 20150713
• Source Data: RiP Project 28745

Subject/Index Terms

• TRT Terms: Box girder bridges; Bridge design; Cantilever bridges; Curling; Hinges; Load and resistance factor design; Load transfer; Prestressing
• Geographic Terms: California
• Subject Areas: Bridges and other structures; Highways;

Filing Info

• Accession Number: 01465979
• Record Type: Research project
• Source Agency: California Department of Transportation
• Files: RIP, STATEDOT
• Created Date: Jan 3 2013 3:08PM