Strength, durability, and application of grouted couplers for integral abutments in ABC projects

Link to:  Final Report

Background
Reduction of road closure times, traffic disruption and user costs, in addition to improvements in construction quality utilizing prefabricated elements, are all qualities of Accelerated Bridge Construction (ABC) that transportation organizations throughout the country find attractive. Taking ABC a step further requires finding means and methods to improve the quality, performance and durability of bridges constructed using ABC. Implementation of quality semi-integral and integral abutment designs in ABC projects is one example. These types of abutments have been used for many years in traditional construction but have seen very limited use in ABC projects. The purpose of this research is to develop integral abutment designs for ABC projects utilizing grouted rebar couplers and evaluate the strength and durability performance of the detail in the laboratory.

Scope
The proposed research will develop integral abutment details utilizing grouted couplers for use in ABC projects and conduct laboratory testing on one or two of the most promising concepts. The following tasks will be performed to achieve the project goals.

  • Task 1 – A detailed review of scientific papers focusing on previous uses of grouted couplers, and integral abutments, in ABC projects. In addition, all relevant developments and design details/requirements for integral abutments used in typical bridge construction.
  • Task 2 – Initially, several details for an integral abutment using grouted couplers will be developed for review by the TAC. Building upon comments from the TAC and contractors familiar with ABC practices/projects, these conceptual designs will be refined, modified and/or eliminated, if needed. Once final designs of the conceptual integral abutment details are drafted, the TAC committee will select one or two of the most promising concepts for evaluation and testing in the laboratory, see Task 3.
  • Task 3 –The integral abutment detail(s) selected in Task 2 will be fabricated in the laboratory for full-scale testing and evaluation. Laboratory testing will resolve to determine the following:
    1. constructability (tolerance) issues, if any, related to the integral abutment joint construction and use of the grouted couplers,
    2. the structural performance of the integral abutment detail in terms of strength, and
    3. the structural performance of the integral abutment detail in terms of durability.
  • Task 4 – A final report will be developed that documents the entire project with a special emphasis on the results of Task 3. More importantly, recommendations for integral abutment details using grouted coupler connections for use in ABC projects will be made.

Research Team
Principal Investigators: Travis Hosteng, Dr. Brent Phares, Professor Terry Wipf, and Dr. Lowell Greimann
Research Assistant: Sam Redd