Legendre polynomial-based stochastic micromechanical model for the unsaturated concrete repaired by EDM

et al. 2020

The (micro-) cracks or (micro-) voids will lead to the damage of concrete material. A stochastic micromechanical framework is proposed to investigate the damage healing of the unsaturated concrete with the electrochemical deposition method. Stochastic micromechanical representations are presented based on the material’s random microstructures. Differential scheme-based multilevel homogenization procedures are proposed to quantitatively predict the effective properties of the repaired concrete. The probability density functions are obtained for the material’s effective properties with an efficient stochastic simulation framework, which is composed of the univariate approximation for the multivariate function, Newton interpolations and Monte Carlo simulations. Numerical examples are employed to verify the proposed stochastic micromechanical framework, which indicates that the presented framework is computationally efficient and capable of describing the electrochemical deposition method healing process for the unsaturated concrete considering the material’s inherent randomness. Finally, the influences of the saturation degrees and the equivalent aspect ratios on the probabilistic behavior of the repaired concrete are discussed on the basis of the proposed models.

Section: Multilevel Homogenization For the Material’s Propertiesmentioning

confidence: 99%

Stochastic micromechanics-based investigations for the damage healing of unsaturated concrete using electrochemical deposition method

et al. 2020

“…It can be found that the current CDHM framework assumes that the properties of the healing material are the same as those of the undamaged matrix. However, the hydration products’ properties are time dependent (Ahmad et al., 2020; Chen et al., 2020b, 2020c; 2020f; Kang and Chen, 2020; Gu et al., 2020; Yang et al., 2020), which implies that the healing material’s properties are not constant and vary with the healing time for the hydration induced self-healing process. To address this issue, a compatible scalar healing variable h* is introduced as below: where m is the parameter considering the property difference between the healing material and the undamaged matrix phase.…”

Section: Hydration Induced Self-healing Descriptionmentioning

confidence: 99%

“…Secondly, define Khp and μhp as the bulk modulus and shear modulus of the hydration products, respectively. They can be attained with the second level homogenization as equations (36) to (49) (Chen et al., 2020a, 2020b) with where Kch, Kcc and Kp denote respectively the bulk modulus of the CH, the cement clinker and the pores; μch, μcc and μp are the shear modulus of these components; vg is the gel matrix’s Poisson's ratio. ϕc…”

Section: The Evolution Of the Hydration Products’ Propertiesmentioning

confidence: 99%

“…Secondly, define K hp and l hp as the bulk modulus and shear modulus of the hydration products, respectively. They can be attained with the second level homogenization as equations ( 36) to (49) (Chen et al, 2020a(Chen et al, , 2020b)…”

Section: The Evolution For the Hydration Products' Propertiesmentioning

confidence: 99%

“…Meanwhile, different micromechanical healing models are proposed for the electrochemical deposition method (EDM) induced self-healing concrete, including the deterministic micromechanical models for the saturated concrete repaired by EDM (Chen et al, 2017a;Chen et al, 2018a) and for the unsaturated concrete repaired by EDM (Chen et al, 2017b;Chen et al, 2018b). Furthermore, to incorporate the inherent randomness of the healed elements, the stochastic micromechanical damage-healing frameworks are established for the repaired saturated concrete (Chen et al, 2019;Chen et al, 2020a) and for the repaired unsaturated concrete (Chen et al, 2020b(Chen et al, , 2020c.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Continuum damage-healing framework for the hydration induced self-healing of the cementitious composite

Liu

et al. 2020

The self-healing materials have become more and more popular due to their active capacity of repairing the (micro-) damages, such as the (micro-) cracks, the (micro-) voids and the other defects. In this paper, the thermodynamic based damage-healing framework is presented for the hydration induced self-healing composite with a compatible healing variable. The new variable is incorporated to consider the time-dependent properties of the hydration products, with which a new damage healing law is proposed. The hydration kinetics are employed to describe the healing process. The properties of the hydration products are arrived with the multiscale and multilevel homogenization scheme. The presented damage-healing model is applied to an isotropic cementitious composite under the tensile loading histories. The presented framework is compared with the classic continuum damage-healing theory and the experimental data. The results show that the presented damage-healing model is capable of describing the hydration induced self-healing of the cementitious composite. It can describe the behavior of the partially and fully healed concrete material. The effects of the healing time and the compatible healing variables on the damage-healing results are investigated based on our proposed framework.

Electrochemical deposition induced continuum damage-healing framework for the cementitious composite

et al. 2021

The electrochemical deposition method is a promising approach to repair the deteriorated concrete in the aqueous environment. In this paper, a continuum damage-healing framework is presented for the electrochemical deposition method based on the multi-field coupling growth process of the electrochemical deposition products. The ion transportation and the electrode reactions are characterized by employing the Nernst-Planck equation and the current conservation equation. The level set method is adopted to capture the growth of the deposition products. Based on the deposition process, a new empirical healing law is presented, with which a new continuum damage-healing framework is presented for electrochemical deposition method. Numerical examples are conducted by applying the presented framework to the damaged cementitious composite under the tensile loadings. The presented framework is compared with the classic continuum damage-healing theory and the experimental data. The results show that the presented models can describe the electrochemical deposition method induced damage-healing for the cementitious composite. Furthermore, the effects of the healing time, the solution concentration and the external voltage on the damage-healing behaviors are investigated based on our proposed framework.