Computation and experimental considerations on dynamic testing of cement mortar

Abstract

Non-destructive tests to assess the dynamic characteristics of the materials are important for both in-situ and laboratory situations. Elastic modulus, rigidity modulus and Poisson ratio can be determined through dynamic testing, by employing resonant frequency measurements. The ASTM C-215 standard contains the necessary information for the experimental set-up and subsequent computation using the longitudinal, transversal and torsional frequencies, for both prismatic and cylindrical specimens. Nevertheless, some experimental particularities are not explained and their influence on the final results might prove important. In this paper, the experimental and computational insights on performing the dynamic Young modulus test for cement mortar prismatic samples, with emphasis on the importance of interpretation of the results are presented. The type of specimen support and the actual data manipulation, when extracting results, are taken into consideration. The results may prove important for the correct employment of dynamic testing.

Effect of a New Multi-Walled CNT (MWCNT) Type on the Strength and Elastic Properties of Cement-Based Mortar

“…The free vibration response of all specimens (nine for each of the mix proportions presented in Table 2) was recorded, as shown in Figure 6a for the Ref mix, using the experimental set-up presented and considerations described in [34]. The fast Fourier transform (FFT) was applied to the recorded signal in order to obtain the response spectrum of the specimens, as shown in Figure 6b.…”