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

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 Phases I and II of this project were mainly focused on: 1) characterizing and modeling novel SMART shear keys under cyclic loads, 2) understanding and evaluating the effect of SMART keys on the seismic behavior of a small-scale bridge bent and a simplified highway bridge subjected to ground accelerations, 3) developing a strategy and algorithm for optimal placement of SMART shear keys, and 4) understanding and developing a similitude law of SMART shear keys for the prediction of their behavior and responses through small-scale model tests. The Phase III of this project is mainly to understand and model the tsunami behavior of bridge superstructures with SMART keys. Specifically, it will conduct small-scale model tests under broken and unbroken waves and develop the drag, lift, and moment coefficients as a function of friction force.

• Record URL:
  https://matc.unl.edu/research/research_project.php?researchID=583

Language

• English

Project

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

  69A3551747107

• 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: 20200323
• Expected Completion Date: 20201231
• Actual Completion Date: 0
• USDOT Program: University Transportation Centers Program
• Source Data: RiP Project 91994-52

Subject/Index Terms

• TRT Terms: Algorithms; Bridge construction; Diaphragms (Engineering); Earthquake resistant design; Girder bridges; Hurricanes; Optimization; Superstructures; Tsunamis
• Subject Areas: Bridges and other structures; Construction; Design; Highways; Maintenance and Preservation;

Filing Info

• Accession Number: 01738627
• Record Type: Research project
• Source Agency: Mid-America Transportation Center
• Contract Numbers: 69A3551747107
• Files: UTC, RIP
• Created Date: Apr 30 2020 3:17PM