Journal
ENGINEERING FRACTURE MECHANICS
Volume 131, Issue -, Pages 557-569Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.engfracmech.2014.09.011
Keywords
Calcium silicate hydrate (C-S-H); Uniaxial tension test; Crack evolution; SCF; DSD
Categories
Funding
- China Ministry of Science and Technology [2015CB655104]
- Chinese National Natural Science Foundation (NSF) [51178230, 51378269]
- Major International Joint Research Project [51420105015]
Ask authors/readers for more resources
Calcium silicate hydrate (C-S-H), the essential binder of cement based materials, is a poor crystal phase at nano-scale. In this study, crack growth mechanism is unraveled in lights of Molecular Dynamics (MD) by simulating the uniaxial tension test on the C-S-H gel with voids ranging from 0.5 nm to 5 nm. At nano-scale, the layered C-S-H gel demonstrates dual nature of crack propagation. In xy plane, the stable ionic-covalent bonds Si-O and Ca-O are hard to break so the cracks coalesce is slowed down, implying ductile characteristic. In z direction, cracks spread in the interlayer region with high rate due to the frequently breakage H-bonds network, exhibiting brittle nature. In the tensile process, the crack develops from the central void and strain concentration'' near the void boundary is induced by irreversible atomic deformation. Young's modulus and tensile strength of C-S-H gel are significantly weakened due to the presence of central void. Additionally, due to the binding constraints' discrepancy, bending of the calcium silicate sheet can be observed, reflecting the complicated tensile behavior of heterogeneous layered C-S-H gel. (C) 2014 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available