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Gan, Yidong (author), Liang, M. (author), Schlangen, E. (author), van Breugel, K. (author), Šavija, B. (author)
This study employs a lattice fracture model to simulate static and fatigue fracture behaviour of Interfacial Transition Zone (ITZ) at microscale and mortar at mesoscale. The heterogeneous microstructure of ITZ and mesostructure of mortar are explicitly considered in the models. The initial step involves calibrating and validating the...
journal article 2024
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Liang, M. (author), He, S. (author), Gan, Yidong (author), Zhang, Hongzhi (author), Chang, Z. (author), Schlangen, E. (author), Šavija, B. (author)
This paper employs computer vision techniques to predict the micromechanical properties (i.e., elastic modulus and hardness) of cement paste based on an input of Backscattered Electron (BSE) images. A dataset comprising 40,000 nanoindentation tests and 40,000 BSE micrographs was built by express nanoindentation test and Scanning Electron...
journal article 2023
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Liang, M. (author), Gan, Y. (author), Chang, Z. (author), Wan, Z. (author), Schlangen, E. (author), Šavija, B. (author)
This study aims to provide an efficient alternative for predicting creep modulus of cement paste based on Deep Convolutional Neural Network (DCNN). First, a microscale lattice model for short-term creep is adopted to build a database that contains 18,920 samples. Then, 3 DCNNs with different consecutive convolutional layers are built to learn...
journal article 2022
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Liang, M. (author), Li, Z. (author), He, S. (author), Chang, Z. (author), Gan, Y. (author), Schlangen, E. (author), Šavija, B. (author)
Stress evolution of restrained concrete is a significant direct index in early-age cracking (EAC) analysis of concrete. This study presents experiments and numerical modelling of the early-age stress evolution of Ground granulated blast furnace slag (GGBFS) concrete, considering the development of autogenous deformation and creep. Temperature...
journal article 2022
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Liang, M. (author), Chang, Z. (author), Wan, Z. (author), Gan, Y. (author), Schlangen, E. (author), Šavija, B. (author)
This study aims to provide an efficient and accurate machine learning (ML) approach for predicting the creep behavior of concrete. Three ensemble machine learning (EML) models are selected in this study: Random Forest (RF), Extreme Gradient Boosting Machine (XGBoost) and Light Gradient Boosting Machine (LGBM). Firstly, the creep data in...
journal article 2022
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Xu, Y. (author), Gan, Y. (author), Chang, Z. (author), Wan, Z. (author), Schlangen, E. (author), Šavija, B. (author)
Tailoring lattice structures is a commonly used method to develop lattice materials with desired mechanical properties. However, for cementitious lattice materials, besides the macroscopic lattice structure, the multi-phase microstructure of cement paste may have substantial impact on the mechanical responses. Therefore, this work proposes a...
journal article 2022
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Liang, M. (author), Chang, Z. (author), He, S. (author), Chen, Y. (author), Gan, Y. (author), Schlangen, E. (author), Šavija, B. (author)
Early-age stress (EAS) is an important index for evaluating the early-age cracking risk of concrete. This paper encompasses a thermo-chemo-mechanical (TCM) model and active ensemble learning (AEL) for predicting the EAS evolution. The TCM model provides the data for the AEL model. First, based on Fourier's law, Arrhenius’ equation, and rate...
journal article 2022
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Gan, Y. (author), Zhang, Hongzhi (author), Liang, M. (author), Zhang, Y. (author), Schlangen, E. (author), van Breugel, K. (author), Šavija, B. (author)
In this study, the flexural strength and fatigue properties of interfacial transition zone (ITZ) were experimentally investigated at the micrometre length scale. The hardened cement paste cantilevers (150 × 150 × 750 μm<sup>3</sup>) attached to a quartzite aggregate surface were prepared and tested under the monotonic and cyclic load using a...
journal article 2022
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Gan, Y. (author), Romero Rodriguez, C. (author), Zhang, Hongzhi (author), Schlangen, E. (author), van Breugel, K. (author), Šavija, B. (author)
This paper presents a method to numerically investigate the microstructural effect on the creep behavior of cement paste at the microscale. The lattice fracture model is extended to consider local time-dependent deformations of calcium-silicate-hydrate phases in the cement paste by imposing local forces. The term “experimentally informed...
journal article 2021
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Gan, Y. (author), Vandamme, Matthieu (author), Chen, Y. (author), Schlangen, E. (author), van Breugel, K. (author), Šavija, B. (author)
This paper presents an experimental investigation on the short-term creep recovery of cement paste at micrometre length scale. Micro-cantilever beams were fabricated and tested with 8 different loading series using the nanoindenter. It is found that cement pastes show high recovery ratios (&gt;80%) even subjected to very high stress levels....
journal article 2021
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Gan, Y. (author), Zhang, Hongzhi (author), Liang, M. (author), Schlangen, E. (author), van Breugel, K. (author), Šavija, B. (author)
In this study, a numerical model using a 2D lattice network is developed to investigate the fatigue behaviour of cement paste at the microscale. Images of 2D microstructures of cement pastes obtained from XCT tests are used as inputs and mapped to the lattice model. Different local mechanical and fatigue properties are assigned to different...
journal article 2021
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Chang, Z. (author), Xu, Y. (author), Chen, Y. (author), Gan, Y. (author), Schlangen, E. (author), Šavija, B. (author)
In this work, the lattice model is applied to study the printing process and quantify the buildability (i.e., the maximum height that can be printed) for 3D concrete printing (3DCP). The model simulates structural failure by incorporating an element birth technique, time-dependent stiffness and strength, printing velocity, non-uniform...
journal article 2021
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Gan, Y. (author), Zhang, Hongzhi (author), Zhang, Y. (author), Xu, Y. (author), Schlangen, E. (author), van Breugel, K. (author), Šavija, B. (author)
This study presents an experimental investigation of fatigue properties of cement paste at the microscale. A strong size dependence is found for the flexural fatigue life of the cement paste specimen. Microscopic observations on the fractured surfaces suggest that there is a higher density of nano-scale cracks generated during the fatigue...
journal article 2021
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Xu, Y. (author), Zhang, H. (author), Gan, Y. (author), Šavija, B. (author)
Cementitious materials are widely used in construction. For their low ductility, they typically need to be reinforced by steel rebars, which cause potential corrosion problems. Polymeric reinforcement, which does not have corrosion problems, has been used to replace steel rebars. However, a relatively high reinforcing ratio is usually...
journal article 2021
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Gan, Y. (author), Romero Rodriguez, C. (author), Schlangen, E. (author), van Breugel, K. (author), Šavija, B. (author)
This study presents an experimental investigation of the rate-dependent mechanical properties of cement paste at the microscale. With the use of a nanoindenter, micro-cantilever beams with the size of 300 μm × 300 μm × 1650 μm were loaded at five different strain rates from around 10<sup>−6</sup>/s to 10<sup>−2</sup>/s until failure. It is...
journal article 2021
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Zhang, H. (author), Xu, Y. (author), Gan, Y. (author), Chang, Z. (author), Schlangen, E. (author), Šavija, B. (author)
Application of micromechanical modelling of hydrated cement paste (HCP) gains more and more interests in the field of cementitious materials. One of the most promising approaches is the use of so-called microstructure informed micromechanical models, which provides a direct link between microstructure and mechanical properties. In order to...
journal article 2020
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Zhang, H. (author), Xu, Y. (author), Gan, Y. (author), Schlangen, E. (author), Šavija, B. (author)
This paper presents a validation process of the developed multi-scale modelling scheme on mortar composites. Special attention was paid to make the material structure of real and virtual mortar specimens comparable at the meso-scale. The input mechanical parameters of cement paste (both bulk cement paste and interfacial transition zone) at the...
journal article 2020
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Zhang, H. (author), Romero Rodriguez, C. (author), Dong, H. (author), Gan, Y. (author), Schlangen, E. (author), Šavija, B. (author)
Carbonation of hydrated cement paste (HCP) causes numerous chemo-mechanical changes in the microstructure, e.g., porosity, strength, elastic modulus, and permeability, which have a significant influence on the durability of concrete structures. Due to its complexity, much is still not understood about the process of carbonation of HCP. The...
journal article 2020
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Gan, Y. (author), Vandamme, Matthieu (author), Zhang, Hongzhi (author), Chen, Y. (author), Schlangen, E. (author), van Breugel, K. (author), Šavija, B. (author)
This study proposes an experimental method for studying the short-term creep behaviour of cement paste at micro-scale. The micro-bending tests on miniaturized cantilever beams were used to characterize the viscoelastic properties of cement paste. The effects of w/b ratio, the type of binder and the stress level on the microscopic creep...
journal article 2020
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Romero Rodriguez, C. (author), França de Mendonça Filho, F. (author), Mercuri, L. (author), Gan, Y. (author), Rossi, E. (author), Anglani, G. (author), Antonaci, P. (author), Schlangen, E. (author), Šavija, B. (author)
In this study, the interface between different types of bacteria-embedded self-healing polylactic acid capsules (PLA) and cement paste is investigated. Particularly, the changes in microstructure and mechanical properties of the interface with respect to bulk cement paste were studied. First, nanoindentation was performed to obtain maps of...
journal article 2020
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