Correlation of Shear Design between AASHTO LRFD Bridge Design Specifications and the AASHTO Guide Specifications

The American Association of State Highway and Transportation Officials (AASHTO) Guide Specifications for the Seismic Design of Bridges was developed to provide a displacement-based approach to the design and construction of conventional bridges. These specifications can apply to all levels of seismic shaking. States like Nevada have not officially adopted the Guide Specifications but use it as part for their designs. The specifications were a result of the performance of bridges during the 1989 Loma Prieta and 1994 Northridge earthquakes. These earthquakes specifically showed vulnerability of reinforced concrete columns to inadequate transverse reinforcement for longitudinal confinement and shear reinforcement. The Guide Specifications works to ensure good shear performance by specifying details that are calculated to provide sufficient displacement/ductility capacity. There have been many experiments and studies that have focused the flexural/bending aspects of column design. The number of studies that investigated shear capacity is substantially less, but they have been used to develop shear equations that are ductility based. The purpose of the project is to investigate the shear capacity of reinforced concrete columns using both the Guide Specifications and the load and resistance factor design (LRFD) Specifications for various levels of axial load, transverse reinforcement and longitudinal reinforcement to determine how the two specifications compare both within the plastic hinge zone and outside the plastic hinge zone for areas throughout Nevada, Arizona and New Mexico. Outside the plastic hinge region, the Guide Specifications permits the designer to use the LRFD Specifications or equations within the Guide Specifications with predetermined values. In order to develop a comprehensive understanding of shear behavior, in addition to examining conventional ASTM A706 and ASTM A615 Grade 60 reinforcement comparison will also be conducted on high strength reinforcement. Experimental data is limited for high strength reinforcement but will provide some test points to compare with the models. The addition of high strength reinforcement enables a consistent examination of shear, plus adds a tool for the designer to use in increasing safety and improving sustainability. As part of the range of the specimens that will be compared, predictions will also be made of the shear capacities of experimental columns given in the PEER Structural Performance Database [Eberhard and Berry]. This will allow not only a comparison between the two methods but also a better understanding their accuracy.

Language

  • English

Project

  • Status: Completed
  • Funding: $61732.00
  • Contract Numbers:

    DTRT-13-G-UTC55

  • Sponsor Organizations:

    Department of Transportation

    Office of the Assistant Secretary for Research and Technology
    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Performing Organizations:

    University of Nevada, Reno

    College of Engineering
    Reno, NV  United States  89557
  • Principal Investigators:

    Sanders, David

  • Start Date: 20141101
  • Expected Completion Date: 0
  • Actual Completion Date: 20160131
  • Source Data: RiP Project 37230

Subject/Index Terms

Filing Info

  • Accession Number: 01539703
  • Record Type: Research project
  • Source Agency: Center for Advanced Transportation Education and Research (CATER)
  • Contract Numbers: DTRT-13-G-UTC55
  • Files: UTC, RiP
  • Created Date: Oct 1 2014 2:16AM