A mechanics based simulation of an RC hinge with FRP reinforcement

Abstract

A common approach to simulating the behaviour of a reinforced concrete member is through the application of the moment-curvature approach. This approach is highly empirical at both the serviceability and ultimate limit state, requiring the determination of an effective flexural rigidity to account for the loss of stiffness due to cracking, and the use of a hinge length to give the rotation which predicts the ultimate deflection. These empirical factors are required as the moment-curvature approach simply cannot simulate the non-material deformation seen in practice, be it cracking or concrete softening. As a direct result of our reliance on these empirical approaches the widespread uptake of new technologies such as brittle FRP reinforcement has been slow as extensive testing must be completed to develop new safe bounds for their use. In contrast to this, a mechanics based moment-rotation approach, which simulates what is seen in practice, that is, the formation of cracks and widening of cracks and the formation of wedges is proposed.