Microstructure-based micromechanical prediction of elastic properties in hydrating cement paste

A micro-fracture model is presented to investigate mechanics properties of porous media such as cement paste on basis of micromechanics theory and fracture theory. Relationships between mechanics properties of porous media and the parameters of pores such as shape, size, and porosity are analysed by this model. Calculation results show that, to a hypothetic porous media with same porosity, the ultimate strength and elastic properties are reduced with an increase of average pore diameter. Nano-scale pores have little effect on the ultimate strength of this porous media while the micron-scale pores have great effect on it. The stress-strain relationship of this porous media with the micron-scaled pores is nonlinear obviously. The results also show that the ultimate strength and elastic properties of the porous media are reduced with an increase of the porosity and shape parameter. Mechanics properties of a cement paste with water cement ratio of 0.5 are tested. The calculation results from the model are in agreement with the experimental results.

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Prediction of Elastic Modulus of Cement-Based Materials Based on Power’s Volume Model

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.253-255.474 ◽

2012 ◽

Vol 253-255 ◽

pp. 474-477 ◽

Cited By ~ 1

Author(s):

Lang Wu ◽

Bing Yan ◽

Bin Lei

Keyword(s):

Elastic Modulus ◽

Elastic Properties ◽

Cement Paste ◽

Cement Ratio ◽

Water Cement Ratio ◽

Micromechanics Model ◽

Volume Model ◽

Cement Based Materials ◽

Hydrated Products ◽

Multi Phase

The hydrated products, unhydrated cement and water (capillary pores) in the cement paste are seen as matrix, inclusion, Equivalent medium respectively, We used the micromechanics theories and Power’s Volume model to develop a multi-phase micromechanics model capable of simulating the elastic properties of cement-based materials, and the evolution of elastic properties in the hydration process was calculated at different water-cement ratio. The final experimental results show that this model can be used to predict the elastic properties of cement-based materials.

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An Efficient Approach of Predicting the Elastic Property of Hydrating Cement Paste

Frontiers in Materials ◽

10.3389/fmats.2021.729644 ◽

2021 ◽

Vol 8 ◽

Author(s):

Baoyu Ma ◽

Guansuo Dui ◽

Zhenglin Jia ◽

Bo Yang ◽

Chunyan Yang ◽

...

Keyword(s):

Elastic Properties ◽

Cement Paste ◽

Volume Fraction ◽

Solid Volume Fraction ◽

Empirical Method ◽

Elastic Behavior ◽

Engineering Practice ◽

Proposed Model ◽

Hydration Model ◽

Semi Empirical

Although elastic properties of hydrating cement paste are crucial in concrete engineering practice, there are only a few widely available models for engineers to predict the elastic behavior of hydrating cement paste. Therefore, in this paper, we derive an analytical model to efficiently predict the elastic properties (e.g., Young’s modulus) of hydrating cement paste. Notably, the proposed model provides the prediction of hydration, percolation, and homogenization of the cement paste, enabling the study of the early age elasticity evolution in cement paste. A hydration model considering the mineral composition and the initial w/c ratio was used, while the percolation threshold was calculated adopting a phenomenological semi-empirical method describing the effects of the solid volume fraction and the w/c ratio. An efficient mixing rule based on the degree of solid connectivity was then adopted to calculate the elastic properties of the hydrating cement paste. Moreover, for ordinary Portland cement, a simplified model was built using Powers’ hydration model. The obtained modeling results are following experimental data and other numerical results available in the literature.

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