Laser Radiation CO2 Effects in Cement Paste at Different Hydration Stages after Preparation

Resumen

"In this work the changes occurring in cement pastes irradiated by 10.6µm CO2 laser at different stages of hydration after preparation are presented. Raman spectroscopy, X-ray diffraction and Scanning Electronic Microscopy (SEM) techniques had been used to observe molecular structural changes. Intensity of cement paste Raman peaks   after laser irradiation was monitored in samples irradiated 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11 days after their preparation. Applied laser power changed Raman peaks intensity at 187.5cm-1, 563cm-1, 695cm-1, 750cm-1, 897cm-1, 1042cm-1 and 1159cm-1 that corresponds to compounds already presents in cement pastes. X ray diffraction, SEM images and changes in the Raman peaks confirm the recrystalization of cement paste compounds into new phases (alite and belite) after irradiation. The produced changes show a clear dependence on the applied laser power density and age of samples."