1 PRESERVATION OF EXISTING BRIDGES IN KENTUCKY USING ADVANCED COMPOSITES Issam HARIK 1 , Tong ZHAO 2 , and Ching Chiaw CHOO 3 Abstract Three bridge retrofitting projects involving the use of advanced composites – Fiber Reinforced Polymer (FRP) – will be briefly discussed in this paper. These applications of FRP composites include the following areas: repairing and strengthening of RC beams due to shear deficiency; flexural strengthening of RC beams due to increased loads; and repairing of PC beams due to the shrinkage. The success and effectiveness of FRP composites illustrated in the aforementioned projects, due to their tremendous advantages over conventional techniques, will definitely elevate their use in many other structural applications in the near future in Kentucky. Keywords: Fiber reinforced polymer (FRP) composites, reinforced/prestressed concrete, bridge, retrofit Introduction According to the National Bridge Inventory Database (FHWA 2003), there are reportedly 591,220 numbers of bridge structures in the United States. Of this number 81,437 are classified as “structurally deficient” and 81,573 are “functionally obsolete”. This indicates that an estimated 28 percents of the nation bridges are in need of repair or replacement. The same database also reveals that 3,997 of 13,461 bridge structures in Kentucky are in either category. The use of advanced Fiber Reinforced Polymer (FRP) composites for repair and rehabilitation is rapidly gaining acceptance worldwide due to their resistance to corrosion, high strength-to-weight ratio, flexibility, etc. Some of the common applications involving FRP composites are: strengthening and repairing of RC and PC beams; repairing of seismic deficient RC columns and piers; and retrofitting of walls and slabs (Avramidou et. al. 1999, Hamilton et. al. 1999, Holloway and Leeming 1999, Hutchinson and Rizkalla 1999, Karbhari et. al. 1999, Norris et. al. 1997, Sonobe et. al. 1999, Tan 1997, Yamakawa et. al. 1999, and Zhao et. al. 2002). This paper intends to showcase some of the bridge preservation projects using FRP composites in the state of Kentucky. Three such projects will be discussed in this paper. These projects include the following areas of FRP applications: shear strengthening of precast prestressed concrete box beams; flexural strengthening of cast-in-place reinforced concrete beams due to increased live loads; and 1 Professor and Chair, Department of Civil Engineering, University of Kentucky, Lexington, KY 40506-0281. E-mail: iharik@engr.uky.edu 2 Visiting Research Professor, Kentucky Transportation Center and Dept. of Civil Engineering, University of Kentucky, Lexington, KY 40506-0281 3 Ph.D. candidate, Department of Civil Engineering, University of Kentucky, Lexington, KY 40506-0281