Suitability of Techniques of FRP Retrofit for Historic URM Buildings

FRP (fiber reinforced polymer) composite retrofit is a practical method for increasing the strength of historic URM buildings. Several materials for FRP upgrading are now available, including using FRP made of glass, aramid, basaltic, and carbon fiber, various resins such as epoxy, polyester, and vinyl ester. In addition to the choices for materials, different retrofit techniques are available, including externally bonded, near-surface mounted, and mechanically anchored FRP. Each of these has strengths and weaknesses for use in historic buildings, related to durability, mechanical compatibility, ease of installation, chemical suitability, seismic ductility, strength, reversibility, and cost. This paper will describe the differences between the various methods of FRP retrofit used for historic building strengthening, describe case studies of FRP installation and performance for historic buildings, and make recommendations for FRP retrofit in relation to the “Standards for Historic Preservation” by the National Park Service.