Calibration patterns for predicting residual strengths of steel fibre reinforced concrete (SFRC)

Steel Fibre Reinforced Concrete (SFRC), a composite construction material, needs reliable prediction and control techniques to promote its use in structural applications. The distribution and orientation of fibres within the concrete matrix plays a major role in the mechanical behaviour of the structural element. Since the observation of those fibres is impossible once the concrete is hardened, new non-destructive testing (NDT) techniques have been developed for its analysis. The application of a magnetic field to the concrete, can lead to check the homogeneity of the material based on the different permeability that provide the fibres according to their distribution and orientation. Based on the mentioned magnetic method, an application oriented correlation is established among these last terms on one hand and the mechanical response of the material on the other. The paper proposes a methodology to infer, non-destructively, the spatial dispersion of mechanical properties throughout the structure. The suitability of the method is assessed comparing the results with Computational Fluid Dynamics (CFD) simulations.