Study of Fine-Grained Cementitious Composites in Solidification Phase Using Acoustic Testing Technique

Study of Fine-Grained Cementitious Composites in Solidification Phase Using Acoustic Testing Technique

en

The paper deals with experimental analysis, which is focused on the use of acoustic measurement during the solidification process. As a material for monitoring was chosen fine-grained cementitious composites in the laboratory environment. For this purpose, a measuring device working on the principle of mechanical waves passing through the material was designed, assembled and verified. The experiment was conducted on cement pastes prepared from CEM I 42.5 R Portland cement with two different water coefficients (w/c = 0.40 and w/c = 0.33). The differences in the wave propagation in cement pastes were investigated. Simultaneously with this experiment, the monitoring and the saving records of the internal temperature was conducted. The results show the time of „critical changes" in the internal structure of the material can be determined. These changes are probably related to the quality of the particle’s bonds in the inner material structure, which is reflected in the propagation of mechanical waves. Overall, it is shown these experiments could be used to expand the understanding of the various processes occurring during early hydration of cement, and the application of these results to field situations (in the future) could lead to the other development of, non-destructive (and nonintrusive) monitoring techniques.

The paper deals with experimental analysis, which is focused on the use of acoustic measurement during the solidification process. As a material for monitoring was chosen fine-grained cementitious composites in the laboratory environment. For this purpose, a measuring device working on the principle of mechanical waves passing through the material was designed, assembled and verified. The experiment was conducted on cement pastes prepared from CEM I 42.5 R Portland cement with two different water coefficients (w/c = 0.40 and w/c = 0.33). The differences in the wave propagation in cement pastes were investigated. Simultaneously with this experiment, the monitoring and the saving records of the internal temperature was conducted. The results show the time of „critical changes" in the internal structure of the material can be determined. These changes are probably related to the quality of the particle’s bonds in the inner material structure, which is reflected in the propagation of mechanical waves. Overall, it is shown these experiments could be used to expand the understanding of the various processes occurring during early hydration of cement, and the application of these results to field situations (in the future) could lead to the other development of, non-destructive (and nonintrusive) monitoring techniques.