A comparative study on the thermal behaviour of PPC and OPC cement

Abstract

Spectroscopy is the interaction between matter and electromagnetic radiation, which is useful in the determination and characterisation of various chemical composition existing in the material. Present paper, focuses on predicting the extent of thermal damage on hydrated Portland Cements ( PC ), using Fourier Transform Infrared Spectroscopy ( FTIR ). The hydrated specimens of Portland Pozzolana Cement ( PPC ) and Ordinary Portland Cement ( OPC ), were subjected to temperatures ranging from 27 °C − 800 °C, for an interval of every 100 °C was analysed. Variation in the absorbance peaks obtained from FTIR , is correlated with the Thermal analysis (TA). At temperatures beyond 400 °C, reduction in the absorbance values at wavenumbers of 3430 – 3440 cm −1 of Ettringite phase for PPC and OPC specimens was observed. However, in OPC specimens, an increase in the absorbance values of Portlandite phase at wavenumbers ranging from 3640 to 3645 cm −1 was observed. The phase changes taking place in the PC specimens observed using FTIR , are in good agreement with the mass loss and heat flow plots obtained from TA. Therefore, it can be concluded that FTIR analysis is suitable test method in predicting the thermal damage of concrete specimen.