New insights into creep characteristics of calcium silicate hydrates at molecular level

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

4 Scopus Citations
View graph of relations

Author(s)

Detail(s)

Original languageEnglish
Article number106366
Journal / PublicationCement and Concrete Research
Volume142
Online published21 Jan 2021
Publication statusPublished - Apr 2021

Abstract

The fundamental mechanisms under concrete creep are far from being fully understood, especially at the molecular level. Hereby, a calcium-silicate-hydrate (C-S-H) molecular model is developed to explain, for the first time, the creep characteristics at various stress states, temperature levels and water contents, which are not accessible experimentally. Rather tensile and compressive loadings, C-S-H only creeps under shear loadings originating from the sliding of the calcium silicate layers over each other as the interlayer component (water and ions) acts as a lubricator. A heterogeneous creep characteristic is observed. Elevated temperature reduces the interlayer lubricator viscosity and weakens the interfacial adhesion between the layers and the interlayer lubricator, which accelerates C-S-H creep. The removal of interlayer water enhances the creep resistance, resulting from the reduced interlayer space and enhanced interfacial adhesion. The atomic-level mechanisms explain the inter-CSH-particle behaviours at the microscale, which bridges the gap between atomistic simulation and microcosmic phenomenon.

Research Area(s)

  • Atomistic simulation, B. Calcium-silicate-hydrate (C-S-H), C. Creep, Temperature, Water content