Nanoscale investigation of the influence of water on the elastic properties of C–S–H gel by molecular simulation

Abstract

Calcium silicate hydrate (C–S–H) gel contains almost 50% to 70% of cement paste, which has a significant effect on the cement paste properties. An attempt is made to assess the atomistic structure of calcium silicate hydrate and the impact of water on it through molecular dynamics simulation. The most similar compositions (tobermorite 14Å, tobermorite 11Å, and jennite) are chosen and the effect of water thereof is studied. This study is presented in two phases: (1) water removal from the structure and simulating difference of water-to-calcium ratios through grand canonical Monte Carlo method. Next, the effect of water on the mechanical properties of C–S–H gel is examined through molecular dynamics method. (2) Defects in the existing molecular structures were introduced, which lead to newer Ca–Si proportions followed by the examination of the effect of water on the new structures. The obtained results revealed that as W/Ca ratio increases, the Young's modulus decreases. An increase in the Ca/Si ratio, owing to the defects in the structure, leads to the reduction in the Young's modulus.

Multi-scale Approach from Atomistic to Macro for Simulation of the Elastic Properties of Cement Paste

“…Zehtab and Tarighat (2016) investigated Diffusion of chloride ions in C-S-H by molecular dynamics method. Tavakoli et al (2017) studied the effect of water on C-S-H properties. Finally, Tavakoli and Tarighat (2016) examined the elastic properties of cement phases.…”

Molecular dynamics investigation of the effect of interlayer cavities of the structure of calcium silicate hydrate at the atomistic scale

“…

Calcium silicate hydrate (CSH) gel, as the most important component of hydration products, has the most significant effect on the properties of hardened cement paste [1,2]. One of the most criticalfactors affecting the mechanical properties of CSHis the interlayer cavities in the gel [3]. In this study, the effect of these cavities on Young's modulus of CSHhasbeen investigated.

…”

Reusing Waste Ceramic and Waste Sanitary Ware in Concrete as Pozzolans with Nano-Silica and Metakaolin

“…Concrete investigation could be experimental or numerical method (Tarighat et al, 2016;Tavakoli et al 2017) that in this study we focus on experimental method. The aim of this research project is the assessment of the mechanical properties of high-strength concrete containing ceramic wastes integration with, nano-silica and metakaolin as a partial replacement for cement.…”