Long-Term Behavior of GFRP Reinforced Panels after Eight Years of Field Exposure

摘要

Since 1998, Missouri S&T/University of Missouri-Rolla investigators have been involved in more than 25 bridge repairs and/or new bridge construction involving composite materials. To date, many of these projects have demonstrated reliable field performance. However, there have been little follow-up investigations to study their residual capacity and behavior after long-term exposure to environmental filed exposure. This study tests and autopsies the Glass Fiber Reinforced Polymers (GFRP) reinforcing bars to examine property behavior after several years of exposure in the field. The GFRP reinforced panels were studied in flexure to examine any degradation in flexural behavior. The six original test panels, undertaken by Branham and Myers, were used for sectional flexural load testing (Four-Point Load Bending Testing) following nearly eight years of seasonal in-situ field exposure. Sample GFRP bar sections were also autopsied to examine the uniaxial tensile characteristics. In addition, Optical Microscopic Image Analysis and Scanning Electron Microscope (SEM) Analysis was conducted to observe if there was any visual signs of de-bonding between the concrete and the reinforcement (steel or GFRP) bars or general deterioration.