With much of today’s infrastructure deteriorating at such a rapid rate, the need for improved methods of design and monitoring are ever more important. This research focuses on the design and monitoring of a full-scale Fiber Reinforced Polymer (FRP) reinforced concrete bridge deck superstructure. A 35 foot Carbon FRP (CFRP) concrete bridge deck and galvanized steel girders design was completed for the replacement of an existing deteriorated superstructure. An integral abutment design was employed to eliminate the need for replacing corrosive expansion joints and bearings in the future as well as increase the rigidity of the superstructure. For reasons related to corrosion, integral abutment designs have become more popular in the northeast for medium to short single span bridges. CFRP bars are used for both primary and temperature (shrinkage) reinforcement in the slab. Additionally, both 180 degree hooks at the ends of the top layer of reinforcement and 90 degree hooks at the abutments are CFRP.

Existing bridge and Fiber Optic Deformation Sensor for proposed monitoring

A long term monitoring system incorporating Fiber Optic Sensors (FOS) to measure the deformations and stresses within the slab and girders is recommended. Due to the absolute uncertainties in much of FRP reinforced concrete design, a long term monitoring system will provide useful insight into the true behavior of the structure. The system will aid verifying specific design measures including but not limited to bond stress values, thermal deformations, and maximum stress readings. Furthermore, the measurements will provide a long term quantitative degradation model to the instrumented components of the structure. Ultimately, a system such as the one proposed will allow researchers and designers a better understanding of the field behavior of FRP reinforced concrete bridge decks. Moreover, incorporating innovative materials such as FRP and galvanized steel will increase the service life of the structure by reducing the need for replacement due to metallic corrosion.

This project is funded by the Federal Highway Administration (FHWA) through the Innovative Bridge Research and Construction (IBRC) program. The IBRC program was started by the FHWA in 1998 to promote the use of innovative materials in bridge structures. The goal of this program is to create longer lasting bridge structures while reducing maintenance and life cycle costs. This particular project was one of two IBRC projects funded in the state of New York in 2004 and one of three in the nation to utilize FRP rebar in the overall design.

Proposed design of replacement superstructure