Reinforcement of concrete with composite materials based on fiberglass

Abstract

Many existing constructions (old and new) have significant deficiencies in terms of load-bearing capacity which, in some cases, could jeopardize the safety of their users. Indeed, we can consider that these structures have arrived (or will arrive very soon) at the end of their useful life, hence the need to find technical and economic solutions to rehabilitate them in the most effective way possible. In the case of reinforced concrete bridges, very many suffer from an advanced state of degradation caused by prolonged exposure to an aggressive environment or even a continuous increase in use loads. In addition, for the old structures, the technical standards used for their design and dimensioning had to be modified from the date of their construction. Thus, certain structural elements in service no longer meet the performance requirements in terms of response to loads. Indeed, it is often less expensive to reinforce the structural elements of structures than to carry out a complete reconstruction, especially since following the evolution of technology, several methods of reinforcement remain available on the market and with prices more and more competitive, including that which consists of the external reinforcement of reinforced concrete elements with composite materials which, due to their strength/weight ratio and their resistance to external agents (non-corrodible product), have very interesting advantages if they are compared to steel whether it is used passively or actively (simple reinforcement or prestressed). In addition, these composite materials can be used both for shear and bending reinforcement for beams and for column containment. This work aims to use (FRP) Fiber Reinforced Plastics (materials generally formed of two main and distinct elements: the fiber "made from Glass" and the matrix "an epoxy resin which allows the transfer of loads between the fibers which improves the properties, in the long and short term"), to assess the influence of glass fibers on the general behavior of concrete, in particular on its resistance, its deformations and its ductility. The results obtained at the end of the cyclic loading tests of the specimens confirm the importance of the contribution that the confinement of the concrete specimens by FRP can bring in terms of resistance to compression and deformation observed following the realization of the static loading tests. However, these cyclic loading tests of the specimens show us the very considerable gain in the ability of the specimens to withstand loading-unloading cycles.