A NUMERICAL INVESTIGATION OF AGGREGATE SHAPE EFFECT ON THE DIFFUSIVITY OF MORTAR BASED ON ELLIPSOIDAL PARTICLE PACKING
Author(s): Liu, L., Chen, H. and Xu, W.
Paper category: Conference
Book title: XIII International Conference on Durability of Building Materials and Components - XIII DBMC
Editor(s): Marco Quattrone, Vanderley M. John
Print ISBN: none
Publication year: 2015
Total Pages: 8
Abstract: The diffusivity of cement-based materials is a key factor related to its service life and durability issue for concrete structures. In recent years, a number of numerical models have been developed to predict the diffusivity of cement-based materials from its corresponding meso-/micro- structures since the great reduction in cost and experimental work. Nevertheless, most modeling works have focused on the packing systems of spherical particles. Investigations about the particle shape effects on the diffusivities of cement-based materials are rarely reported. Based on ellipsoidal particles packing, by coupling with a 3D lattice approach, the aggregate shape effects on the diffusivities of mortar are studied in this paper. By the random packing model of ellipsoidal particles, mortars with aggregates of different aspect ratios (e.g. κ =0.4, 0.6, 0.8, 1, 2, 3) are obtained first. Then, the mesostructures of mortars are digitalized by a specific algorithm. Consequently, 3D lattice networks composed of diffusive lattice elements are constructed from the digital mesostructures of mortars. From the 3D lattice networks, the diffusivities of mortars can be predicted. The simulations are compared with experimental results. Finally, the dependences of mortar diffusivities on the aggregate shapes at various aggregate volume fractions are discussed. The influences of ITZ zone on the diffusivities of mortars of aggregates of different aspect ratios are also discussed.
Online publication: 2015
Publication Type: full_text
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