A micromechanical investigation of cement paste through a combination of the X-ray computed tomography and the phase field method

Abstract

Micromechanical modeling could provide essential insights into the failure mechanisms within cement paste, which is important for assessing and enhancing the performance of concrete. This study proposes a novel micromechanical modeling framework manifesting itself as a combination of the X-ray computed tomography for characterizing and the phase field method for modeling. Different from previous attempts, the procedure of the phase segmentation in cement paste is not necessary herein, thus reducing uncertainty in the microstructural characterization as well as the parametric input of the micromechanical modeling. The micromechanical modeling framework is used to predict the entire fracture process of cement paste. The current results are compared with previous studies for the sake of validation. Two critical parameters reflecting the micromechanical behavior are extracted and discussed, i.e., Young's modulus and tensile strength. Special attention is spent on the size effect of these parameters.