不同钙硅比水化硅酸钙力学性能的分子动力学模拟<sup>*</sup>

doi:10.11896/j.issn.1005-023X.2017.020.032

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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.

Key words： molecular dynamics calcium silicate hydrate calcium-to-silicon ratio mechanical properties

Published: 05 May 2018

CLC number:	O561.2
	O341

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	Articles by authors
	LIN Weihui
	FU Jia
	WANG Zhihua
	XIN Hao

Cite this article:

LIN Weihui,FU Jia,WANG Zhihua, et al. Molecular Dynamics Simulations of Mechanical Properties of C-S-H Structures with Varying Calcium-to-Silicon Ratios[J]. Materials Reports, 2017, 31(20): 158-163.

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http://www.mater-rep.com/EN/10.11896/j.issn.1005-023X.2017.020.032 OR http://www.mater-rep.com/EN/Y2017/V31/I20/158

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