Innovative Strengthening for Deteriorated Concrete Bridges Using Embedded Composite Sheets Bonded with Polyester-Silica

This report presents the feasibility of a novel anchor system that mitigates the end-peeling of carbon fiber reinforced polymer (CFRP) sheets used for strengthening reinforced concrete beams. Contrary to conventional anchoring methods, CFRP sheets are embedded inside the pre-grooved concrete and covered by a durable polyester-silica composite. After conducting ancillary tests on material, bond, and interfacial properties, 14 strengthened beams are loaded in flexure to assess the performance of the proposed anchor system, contingent upon embedment angle and local debonding along the bond-line. The polyester-silica matrix shows superior moisture-resistance to ordinary cementitious mortar and possesses a fully-cured compressive strength of 38 MPa as well as interfacial capacities comparable to those of an epoxy adhesive. The embedment angle and local debonding of CFRP affect the flexural behavior of the strengthened beams, including sectional rotation and stress distributions. The presence of mechanical fasteners with supplementary epoxy layers in the anchorage substantially enhances the flexural capacity, energy dissipation, and ductility of the beams. Correlation and sensitivity analyses are performed to analytically characterize the load-carrying capacities of the strengthened beams with variable embedment angles and the degree of local debonding.

• Record URL:
  https://www.ugpti.org/resources/reports/details.php?id=983
• Supplemental Notes:
  • This document was sponsored by the U.S. Department of Transportation, University Transportation Centers Program.
• Corporate Authors:

  University of Colorado, Denver

  Department of Civil Engineering
  1200 Larimer Street, P.O. Box 173364
  Denver, CO  United States  80217-3364

  Mountain-Plains Consortium

  North Dakota State University
  Fargo, ND  United States  58108

  Office of the Assistant Secretary for Research and Technology

  University Transportation Centers Program
  Department of Transportation
  Washington, DC  United States  20590
• Authors:
  • Kim, Yail Jimmy
• Publication Date: 2019-12

Language

• English

Media Info

• Media Type: Digital/other
• Features: Appendices; Figures; Photos; References; Tables;
• Pagination: 30p

Subject/Index Terms

• TRT Terms: Beams; Bond strength (Materials); Composite materials; Compressive strength; Concrete bridges; Debonding; Feasibility analysis; Fiber reinforced polymers; Flexural strength; Sensitivity analysis; Sheets; Structural strengthening
• Subject Areas: Bridges and other structures; Highways; Maintenance and Preservation; Materials;

Filing Info

• Accession Number: 01733986
• Record Type: Publication
• Report/Paper Numbers: MPC-19-409
• Contract Numbers: MPC-516
• Files: UTC, TRIS, ATRI, USDOT
• Created Date: Mar 20 2020 4:24PM