SMART Shear Keys for Multi-Hazards Mitigation of Diaphragm-Free Girder Bridges – Phase II

The goal of this multi-phase project is to prevent the out-of-plane rupture of concrete girders and flexural damage to lateral restrainers under earthquake loads and floated-and-displaced bridge superstructures under hurricane events by exploring and developing a novel concept of diaphragm-free girder bridges with Sliding, Modular, Adaptive, Replaceable, and Two-dimensional (SMART) shear keys. Each key is composed of three precast concrete modules arranged in an L-shape that are horizontally and vertically post-tensioned with replaceable unbonded steel bars to form two wedged sliding surfaces. When installed next to a girder and anchored into its capbeam support, the key provides controllable horizontal and vertical friction forces during natural hazards and regulates corresponding displacements over time. The first phase aims to: (1) characterize novel SMART shear keys under cyclic loads, (2) develop a friction-gap model of the shear keys for inclusion in computational modeling and simulation of bridges, and (3) understand and evaluate the effect of SMART keys on the seismic behavior of a small-scale bridge bent subjected to ground accelerations. The objectives of this research are: (1) to understand the system behavior and responses of a simplified highway bridge, particularly the torsional effect of spatially-distributed SMART shear keys under strong multi-component earthquakes, and (2) to develop a strategy and algorithm for optimal placement of SMART shear keys, and to understand and develop a similitude law of SMART shear keys for the prediction of their behavior and responses through small-scale model tests.


  • English


  • Status: Completed
  • Funding: $164918
  • Contract Numbers:


  • Sponsor Organizations:

    Office of the Assistant Secretary for Research and Technology

    University Transportation Centers Program
    Department of Transportation
    Washington, DC  United States  20590

    Mid-America Transportation Center

    University of Nebraska-Lincoln
    2200 Vine Street, PO Box 830851
    Lincoln, NE  United States  68583-0851
  • Managing Organizations:

    Mid-America Transportation Center

    University of Nebraska-Lincoln
    2200 Vine Street, PO Box 830851
    Lincoln, NE  United States  68583-0851
  • Project Managers:

    Stearns, Amy

  • Performing Organizations:

    Missouri University of Science & Technology, Rolla

    Department of Engineering
    202 University Center
    Rolla, MO    65409
  • Principal Investigators:

    Chen, Genda

  • Start Date: 20190101
  • Expected Completion Date: 20191231
  • Actual Completion Date: 20220630
  • USDOT Program: University Transportation Centers Program
  • Source Data: 91994-29

Subject/Index Terms

Filing Info

  • Accession Number: 01692266
  • Record Type: Research project
  • Source Agency: Mid-America Transportation Center
  • Contract Numbers: 69A3551747107
  • Files: UTC, RIP
  • Created Date: Feb 5 2019 4:24PM