Numerical study of the initial particle parking structure of cement/geopolymer pastes and dissolution of amorphous silica using real-shape particles

Published

December 12, 2017

Author(s)

Edward Garboczi, Yibing Zuo, Zhiwei Qian, Guang Ye

Abstract

Many particle-based numerical models have been used to simulate the hydration process of cementitious materials. But most of these models employ regular shape particles, such as spheres, to represent cement, slag or fly ash, which neglect the influence of particle shape. To deal with this issue, this study used irregular shape particles to simulate the initial particle parking structure of cement/geopolymer pastes. The irregular shapes of cement, slag and fly ash particles are characterized by spherical harmonic series. The initial particle parking structures of the pastes of binary blended binders using cement, slag or fly ash at water (liquid) to binder ratio of 0.5 were simulated and compared to those of neat binder pastes. The amount of particles placed in each sieve range and the total amount agree with the target ones for most simulated initial particle parking structures. As a demonstration, the initial particle parking structure of amorphous silica in alkaline solution was generated using irregular shape particles, and was used as input to simulate the dissolution of silica particles. The Lattice Boltzmann method was used to simulate the transport of aqueous ions and thermodynamics was used to consider the rate of dissolution of silica particles. The dissolved fractions of silica at different temperatures in the simulation agree very well with experimental measurements. The influences of the concentration of alkali and the particle shape on the dissolution kinetics of silica particles were also investigated numerically.

Proceedings Title

Proceedings of the 9th International Symposium on Cement and Concrete

Conference Dates

October 31-November 3, 2017

Conference Location

Wuhan, CN

Pub Type

Conferences

Keywords

numerical simulation, initial particle parking structure, cement/geopolymer paste, dissolution, amorphous silica

Citation

Garboczi, E. , Zuo, Y. , Qian, Z. and Ye, G. (2017), Numerical study of the initial particle parking structure of cement/geopolymer pastes and dissolution of amorphous silica using real-shape particles, Proceedings of the 9th International Symposium on Cement and Concrete, Wuhan, CN (Accessed March 13, 2025)