FRCM Systems : The Second Generation of Externally-Bonded Composite Systems for Strengthening of Concrete and Masonry Structures

After overcoming the initial growing pains (insufficient experience, track record, and knowledge overshadowed by overzealous euphoria with “magic” material capabilities), externally-bonded fiber reinforced polymer (FRP) systems have become one of the preferred technologies for repair and strengthening of concrete and masonry structures in the United States. FRP systems have features such as high tensile strength, light weight, relative ease of installation, and resistance to corrosion, which make them attractive to the repair industry. However, FRP also has limitations, which can preclude their use in some applications. For instance, high temperatures compromise the efficiency of FRP systems, FRP applications are limited on moist surfaces or at low temperatures, and FRP systems typically act as a vapor barrier.|These drawbacks are all related to the epoxy matrix used to embed and bond the fibers. Thus, substituting the epoxy matrix with a cementitious matrix appeared to be the most reasonable solution to improve the overall performance of externally-bonded composite systems. This new generation of composite systems is known as fabric reinforced cementitious matrix (FRCM). FRCM developed as an evolution of ferrocement, where the mortar matrix is reinforced with open meshes of continuous dry fibers. In the literature, FRCM is also known as Textile Reinforced Concrete (TRC), or Textile Reinforced Mortar (TRM). The first use of TRC and TRM was reported in Europe in the late 1990s in new construction applications such as permanent formworks elements, facades, tanks and containment.

Read the article.