Measurement of Young's modulus of cementitious materials using an electro-optic holographic technique

Abstract The electro-optic holographic technique has already been used to determine Young's dynamic modulus in homogeneous materials based on the resonance frequency of the analysed samples. This paper shows a modification of the determination method of this frequency that speeds up this process thus obtaining Young's modulus. Based on the visualisation of real time fringes drawn by exciting the rods at the 1000–10,000 Hz range, the proposed method allows us to determine their resonance frequencies. This procedure has been used in the analysis of non-homogeneous materials such as mortar and concrete. The results obtained by this method show good correlation with those determined by the conventional compression method established by Una Norma Espanola (UNE) regulations, but with a smaller variability as far as measurements are concerned. The variation coefficient is less than 1% with the optical method as opposed to 3% with the compression technique.