COMPUTATIONAL SIMULATION |
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Molecular Dynamics Simulations of Mechanical Properties of C-S-H Structures with Varying Calcium-to-Silicon Ratios |
LIN Weihui1, FU Jia2, WANG Zhihua1, XIN Hao1
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1 Shanxi Key Lab. of Material Strength & Structural Impact, Institute of Applied Mechanics and Biomedical Engineering, Taiyuan University of Technology, Taiyuan 030024; 2 Laboratoire de Génie Civil et Génie Mécanique, INSA de Rennes, Rennes 35708 |
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Abstract The atomic structures of calcium silicate hydrate (C-S-H) with varying calcium-to-silicon (C/S) ratios were constructed by the cCSH models of Pellenq et al., and the mechanical properties of C-S-H structures under tensile loading were investigated using molecular dynamics (MD) method. The results from the molecular dynamics simulations showed that the tensile strength was decreased significantly when the C/S ratio was greater than 1.0, compared to the case of C/S=1.0. The interaction between calcium atoms and oxygen atoms played an important role under loading, which made up the shortfall caused by the lack of SiO2, and the decrease of the strength of C-S-H in the case of C/S>1.0 became slow. The water molecules helped to cut off the interaction between calcium atoms and oxygen atoms at a certain deformation degree, which reduced the strength of C-S-H till to the failure mode.
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Published: 25 October 2017
Online: 2018-05-05
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