Research Activities: 2006

Design of FRP Systems for Strengthening Concrete Girders in Shear: Phase I



*Final report to be posted at the completion of R197

Sequential Number


Matching Research Agency

Transportation Research Board


Principal Investigator

Belarbi, Abdeldjelil
Distinguished Professor of Civil Engineering
University of Missouri-Rolla
Room CE 323, UMR
Rolla, MO 65409

p(573) 341-4478
f(573) 341-4729

Student Involvement

1 MS and 1 Post-Doc


Project Objectives

The objective of this project is to develop design methods, specifications, and examples for design of FRP systems for strengthening concrete girders in shear.


Project Abstract

FRP systems have been used on a project-specific basis for the last two decades. They are now becoming a widely accepted method of strengthening concrete structures. The acceptance and utilization of these new strengthening techniques depend on the availability of clear design guidelines, installation procedures and construction specifications. Standard specifications exist for all commonly used traditional materials in civil engineering structures. At this time, design specifications for FRP use are still under development. The results of several experimental investigations have shown that FRP systems can be effective for increasing ductility and strength to structural members such as columns and girders. As most of the research focused on strengthening of axial members of flexural members, there are less experimental and analytical data on the use of FRP systems for shear strengthening of girders. Shear strengthening with FRP is still under investigation and the results obtained thus far are scarce and sometimes controversial. Even in traditional reinforced concrete members without FRP, the shear design is a complex challenge and uses more empirical methods as compared to axial and flexural design methods. Adding FRP to the equation, with its specific design issues, would bring another level of complication in the design. These FRP-related shear design issues and lack of comprehensive analytical and experimental models are the main motivation for this research project. Thus, a thorough understanding of the shear design problem along with the development of an AASHTO design method for FRP shear strengthening of concrete girders are needed.

As such, the objective of this project is to develop design methods, specifications, and examples for design of FRP systems for strengthening concrete girders in shear. The proposed specifications will be in LRFD format and will be suitable for recommendation to the AASHTO Highway Subcommittee on Bridges and Structures for adoption.

Anticipated Benefits

Provide bridge designers with design methodologies and equations, and examples to help for the use of FRP for shear strengthening of RC and PC girders.


Modal Orientation

Bridge Assessment: Bridges testing and bridge strengthening for shear using FRP



Project Start Date:


Project End Date:07/31/2009

Relationship to other Research/Projects



Technology Transfer Activities

The AASHTO membership states are the primary audience for this project. The target audience and market includes bridge owners and bridge designers, federal and state DOT representatives, bridge construction inspectors, general contractors, and the broader research community and to some extent the instructors and students in educational institutions.

The PI's will take a proactive role and make necessary presentations to assist in explaining and promoting the proposed design guidelines. In addition, the PI's will promote these research products at conferences, technical meetings, seminars, workshops and other professional gatherings and to AASHTO technical committees. The PI's will organize a half-day workshop at TRB meeting to summarize the research findings and outline the proposed design and analysis procedures as well as design examples related to this research project.


Transportation Research Board Keywords

Bridge, Bridge Girders, FRP Strengthening