Evaluation of elastic modulus of cement paste corroded in bring solution with advanced homogenization method

Abstract

This paper presents an integrated investigation of elastic modulus of corroded cement paste by experiments and homogenization calculation. First of all, cured cement paste samples were immersed in brine solution with specific chemical compositions for 60d. Then the elastic moduli of the samples were measured by the nanoindentation test. The test results demonstrated that the elastic moduli of the nanoindentation points decreased, compared with the original cement paste. In addition, X-ray Diffraction (XRD) and Scanning Electron Microscope-Energy Dispersive Spectroscope (SEM-EDS) were combined to analyze the compositions of the corroded cement paste quantitatively. As a result, volume fractions of nine compositions of the corroded cement paste in each nanoindentation point were calculated. Afterward, an advanced homogenization method combining Mori-Tanaka (MT) method with self-consistent (SC) method was proposed to calculate the elastic moduli of the nanoindentation points. The calculation results had good agreement with the experimental results due to small relative difference and standard deviation. The back-scattered electron (BSE) image was used to analyze the elastic moduli distribution of the nanoindentation points as well. The result indicated that the elastic moduli of the nanoindentation points were related to the elastic moduli of their main compositions.