Durability study on RC beams strengthened with BFRP fabric

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Our economy largely depends on the performance of bridges, which ensure the connectivity among our cities and towns. Many bridges in Canada were built in the 1940s and 1950s and hence, the majority of these bridges have exceeded or will soon exceed their service life. Further, many of the bridges were designed for vehicle loads much less than current vehicle loads. The primary reason for this is that current commercial and farming vehicles are much heavier and greater in size than those operated in the 1940s and 1950s. Many of these bridges were built using cement concrete and others were built with structural steel or timber. Nonetheless, these bridges need immediate attention for strengthening and/or rehabilitation if they are to be kept in service for an extended period beyond their designed service life. An alternative solution would be to replace these bridges with new bridges; however, this is not an economically viable solution since this would cost trillions of tax dollars. Hence, researchers around the world have been exploring a low-cost and easy-to-apply rehabilitation and strengthening technique that can be adopted with minimum interruption to the traffic flow. This new rehabilitation and strengthening technique uses various fibre reinforced polymer (FRP) fabrics which are attached to the members of a bridge using strong structural adhesive. Researches, in general, have shown that this rehabilitation technique is able to restore the strength and this strengthening technique is able to provide additional strength required to support heavier vehicles. These studies, however, did not pay attention to the durability and long-term performance of the members rehabilitated and/or strengthened using FRP fabrics. Hence, the proposed NSERC project will take a bold step to determine the durability and long-term structural performance of concrete beams (girders) when strengthened using FRP fabric. This research will focus on concrete bridge girders strengthened with basalt FRP fabric, which is an emerging, cheaper, and greener FRP material.