Bonded and Mechanically Fastened FRP Strengthening Systems: A Case Study

Synopsis: This paper describes a case study addressing analysis, design, installation, load rating, load testing, numerical verification and monitoring of the strengthening of an old deficient bridge under a field validation research project. The strengthening was performed by means of two composite technologies: the common manual lay-up CFRP system and a mechanically fastened FRP (MF-FRP) system. The later consisted of precured FRP laminates having high transverse bearing strength (i.e., bidirectional fibers) attached to the structural element by means of wedge anchors. Although considered a temporary solution, the technique is attractive because it requires minimum surface preparation. The bridge will be monitored for 5 years to evaluate the long-term performance of the techniques. In this sense, load tests were performed to evaluate the bridge structural behavior prior to and after the strengthening, showing that the rehabilitation performed as predicted by numerical analysis and therefore created the possibility to remove the bridge load posting.