Calibration of wall effects in mesostructure modelling of concrete using marker-controlled watershed segmentation

Abstract

This paper proposes formulae for refined models that account for wall effects when modelling the geometric mesostructure of concrete. The wall effect should be taken into account in the mesostructure modelling of concrete since it affects the spatial distribution and packing of aggregates within concrete elements. However, scarce research has focused on the calibration of the wall effect in geometric modelling. Measurements on sections of real specimens using the marker-controlled watershed segmentation (MCWS) method are used to accurately identify aggregate particles from digital images and these data are used to calibrate and validate the proposed formulae. The distance and diameters of aggregates relevant to wall effect were obtained and a distribution factor γ that can control the minimum gaps surrounding the particles was calibrated. A demonstrative application of the refined wall effect model shows that the mesostructure modelled agrees well with the experimental data.