A Calibration Method of Meso-Parameters of Cement Mortar Based on the Discrete Element Method

Meso-parameters are key factors of numerical simulation based on the discrete element method (DEM). For cement mortar, the unconfined compressive strength test was simulated by the two-dimensional particle flow code (PFC2D). The influences of the main meso-parameters of the linear parallel bond model, including
$\boldsymbol{\overline{E}^{\ast}, \overline{\sigma}_{c}, \overline{c}, \overline{\kappa}^{\ast}}$
and
$\mu$
, on unconfined compressive strength, elastic modulus and Poisson's ratio were studied. The results show that unconfined compressive strength, elastic modulus, and Poisson's ratio are mainly influenced by the cementing force (
$\overline{\sigma}_{c}$
and
$\bar{c}$
),
$\overline{E}^{\ast}$
, and
$\overline{\kappa}^{\ast}$
, respectively. Then, a calibration method was proposed and validated, based on the meso-parameters determined by the method, unconfined compressive strength, elastic modulus, and Poisson's ratio can be accurately predicted.