Application of micro-CT to Mori-Tanaka method for non-randomly oriented pores in air-entrained cement pastes

Abstract

The homogenization technique has played a key role in elucidating the mechanical, thermal, and chemical behaviors of composite materials. Specifically, the cement-based material is a representatively complex composite material consisting of various inclusions, such as pores, fibers, and aggregates. Recent studies have mathematically introduced the Mori-Tanaka method to express non-randomly oriented ellipsoidal inclusions. Therefore, the present study aimed to practically apply pore information obtained from micro-computed tomography (micro-CT) to the Mori-Tanaka method. Cement-paste samples were prepared with 0, 1, 2, 5, and 10 wt% of an air-entraining (AE) agent. The representative ellipsoidal shape and orientation distribution function (ODF) of the pores were obtained from the micro-CT, and this information was incorporated into the Mori-Tanaka method. The computation results revealed good agreement between the results of the Mori-Tanaka method and the finite-element method (FEM). Additional sensitivity studies using the Mori-Tanaka model allowed for quantifying the anisotropic degree of the pores in the AE-agent added cement pastes.