Micromechanical framework for saturated concrete repaired by the electrochemical deposition method with interfacial transition zone effects

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

Chen

Zhu

et al. 2020

“…To date, many literatures have been published on EDM, which mainly focus on the experimental research (Chang et al., 2009; Chen, 2014; Otsuki and Ryu, 2001; Otsuki et al., 1999; Ryu, 2003; Ryu and Otsuki, 2002, 2005). Recently, the effective medium-based micromechanical framework was presented to obtain the effective linear elastic properties of concrete repaired by EDM, which is promising to disclose the EDM healing mechanism from a theoretical approach (Chen et al., 2015b, 2015c, 2016a, 2017a, 2018c, 2018d; Zhu et al., 2014).…”

Section: Introductionmentioning

confidence: 99%

Stochastic micromechanical predictions for the probabilistic behavior of saturated concrete repaired by the electrochemical deposition method

Chen

Zhu

et al. 2019

Self Cite

A stochastic micromechanical framework is proposed to quantitatively characterize the probabilistic behavior of the mechanical performance of the saturated concrete healed by the electrochemical deposition method. Micromechanical model for the healed saturated concrete is presented based on the material microstructures, and new multilevel homogenization procedures are proposed to quantitatively predict the effective properties of the repaired concrete considering the inter-particle interactions. The evolutions of the deposition products are characterized by non-stationary random process, which is represented by Karhunen–Loeve approximations with limited random variables. The probabilistic behavior for the effective properties of the repaired concrete is reached by incorporating the maximum entropy principle and Monte Carlo simulations. The predictions obtained by the proposed stochastic micromechanical framework are then compared with the available experimental data, existing models, and commonly used probability density functions, which indicate that the presented stochastic micromechanical framework is capable of describing the electrochemical deposition method healing process, considering the inherent randomness of the material microstructures. Finally, the influences of the deposition products on the probabilistic behavior of the repaired concrete are discussed on the basis of the proposed models.

“…However, for frozen soils, few attempts were made to consider the microstructures by means of continuum micromechanics and homogenization theory of heterogeneous materials. During the last decades, many researchers have made investigations on unfrozen reinforced composite materials, mainly focusing on the interactions between the matrix and inclusions in micro-scale perspective to simulate the macroscopic stress–strain responses (Ayadi et al., 2018; Chen et al., 2017; Damiani and Sun, 2017; Diamantopoulou et al., 2017; Egner and Ryś, 2017; Ganjiani, 2018; Hassanifard and Feyzi, 2017; Jin and Arson, 2018; Mizuno, 2017; Park et al., 2017; Pupurs and Varna, 2017; Wu and Ju, 2017; Zhang et al., 2017). Sun et al.…”

Section: Introductionmentioning

confidence: 99%

A micromechanics-based elastoplastic constitutive model for frozen sands based on homogenization theory

Liu

2019

A micromechanics-based constitutive model is formulated to describe the nonlinear elastoplastic behaviors of frozen sands. In the model, frozen soils are conceptualized as two-phase materials, in which the first phase is regarded as virgin/undamaged frozen soil specimen including the components of soil particles, ice crystals, and partial water with elastic–brittle behaviors (bonded elements), and the second phase is treated as fully damaged soil sample including soil particles and unfrozen water with elastoplastic behaviors (frictional elements). The interactions between bonded elements and frictional elements are well considered in the representative volume element within the framework of continuum micromechanics and homogenization theory. Moreover, the non-uniform distribution of strain is taken into account and the breakage process is considered due to the structural degradation/loss of ice crystals in the representative volume element. It is found that the ice crystals are gradually breaking up and then melting into unfrozen water with the increase of external loads, so at the moment the bonded elements are considered to transform into frictional elements and then both elements bear the external loads collectively. A novel binary-medium constitutive model is established by the Mori–Tanaka technique and then validated by two groups of laboratory tests about frozen soils and unfrozen sands under conventional triaxial compression conditions. Eventually, the predictions demonstrate that the theoretical calibrations are well in agreement with the available experimental stress–strain responses.