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Zhang, H. (author), Šavija, B. (author), Chaves Figueiredo, S. (author), Lukovic, M. (author), Schlangen, E. (author)
This work aims to provide a method for numerically and experimentally investigating the fracture mechanism of cement paste at the microscale. For this purpose, a new procedure was proposed to prepare micro cement paste cubes (100 × 100 × 100 µm3) and beams with a square cross section of 400 × 400 µm2. By loading the cubes to failure with a...
journal article 2016
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Šavija, B. (author), Zhang, H. (author), Schlangen, E. (author)
Excessive cracking can be a serious durability problem for reinforced concrete structures. In recent years, addition of microencapsulated phase change materials (PCMs) to concrete has been proposed as a possible solution to crack formation related to temperature gradients. However, the addition of PCM microcapsules to cementitious materials...
journal article 2017
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Zhang, H. (author), Šavija, B. (author), Schlangen, E. (author)
This work proposes a new method for micromechanical simulation of cement paste based on a combination of statistical nanoindentation and XCT technique without the need for explicit identification of distinct phases. A linear relationship between the greyscale level and local Young’s modulus was assumed and verified by the two-sample Kolmogorov...
conference paper 2018
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Zhang, H. (author), Šavija, B. (author), Schlangen, E. (author)
The aim of this paper is to investigate the fracture performance of cement paste at micro scale by both experimental and numerical methods. Micro cubic specimens with length of 100 µm were fabricated by precision cutting, grinding and micro-dicing, and tested by splitting with a wedge tip mounted on a nano-indenter. A nominal splitting...
journal article 2018
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Zhang, H. (author), Šavija, B. (author), Xu, Y. (author), Schlangen, E. (author)
Cement paste possesses complex microstructural features including defects/pores over a range of length-scales, from nanometres to millimetres in size. As a consequence, it exhibits different behaviour under loading depending on the size. In this work, cubic specimens in a size range of 1: 400 were produced and tested by a one-sided splitting...
journal article 2018
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Gan, Y. (author), Zhang, H. (author), Šavija, B. (author), Schlangen, E. (author), van Breugel, K. (author)
Cement paste is the main binding component in concrete and thus its fundamental properties are of great significance for understanding the fracture behaviour as well as the ageing process of concrete. One major aim of this paper is to characterize the micromechanical properties of cement paste with the aid of a nanoindenter. Besides, this paper...
journal article 2018
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Zhang, H. (author), Schlangen, E. (author), Šavija, B. (author)
Cement paste is the glue that holds concrete together and any improvements in material performance will come from its microstructure. For better understanding and predicting its elastic properties and fracture performance, more and more studies are carried out based on micromechanics simulations. However, the predicted results can be hardly...
conference paper 2018
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Zhang, H. (author), Šavija, B. (author), Schlangen, E. (author)
This work presents a study of stochastic fracture properties of cement paste at the micro length scale based on a combination of X-ray computed tomography (XCT) technique and discrete lattice type fracture model. Thirty virtual specimens consisting of pore, outer hydration products, inner hydration products and anhydrous cement particles were...
journal article 2018
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Zhang, H. (author), Schlangen, E. (author), Šavija, B. (author)
This work aims to investigate the mechanical properties of the cement paste-aggregate interface by combining experimental and numerical approaches. The multi-phase interface microstructure was obtained by X-ray computed tomography (XCT) and submitted to a discrete fracture lattice model for fracture analysis. Apart from the modelling, a...
conference paper 2019
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Chang, Z. (author), Zhang, H. (author), Schlangen, E. (author), Šavija, B. (author)
The aim of this work is to investigate the fracture process of concrete under various boundary conditions. Although numerous concrete fracture tests have been reported, showing the failure behavior of concrete, their evaluation is ambiguous due to the limitations of specimen size and experimental conditions. Therefore, it is necessary to use...
conference paper 2019
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Gan, Y. (author), Zhang, H. (author), Šavija, B. (author), Schlangen, E. (author), van Breugel, K. (author)
Nanoindentation is usually used to investigate local elastic properties and hardness of materials. In this paper, the nanoindenter served as a loading tool to perform micro scale bending tests and measure the global response of micro-scale specimens. For testing, cement paste cantilever beams with a square cross-section of 300 μm × 300 μm were...
conference paper 2019
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Zhang, H. (author), Xu, Y. (author), Gan, Y. (author), Chang, Z. (author), Schlangen, E. (author), Šavija, B. (author)
The aim of this work is to investigate the mechanical performance of hardened cement paste (HCP) under compression at the micrometre length scale. In order to achieve this, both experimental and numerical approaches were applied. In the experimental part, micrometre sized HCP specimens were fabricated and subjected to uniaxial compression by...
journal article 2019
document
Šavija, B. (author), Zhang, H. (author), Schlangen, E. (author)
Properties of concrete are, to a large extent, dependent on the properties of its binding constituent, hydrated cement paste. Therefore, knowledge of properties of hydrated cement paste is crucial for predicting concrete behavior. This paper presents an experimentally informed approach for modeling elastic and transport properties of cement...
journal article 2019
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Zhang, H. (author), Gan, Y. (author), Xu, Y. (author), Zhang, Shizhe (author), Schlangen, E. (author), Šavija, B. (author)
The aim of this work is to predict the micromechanical properties of interfacial transition zone (ITZ) by combining experimental and numerical approaches. In the experimental part, hardened cement paste (HCP) cantilevers (200 μm × 100 μm × 100 μm) attached to a quartzite aggregate were fabricated and tested using micro-dicing saw and...
journal article 2019
document
Zhang, H. (author), Šavija, B. (author), Lukovic, M. (author), Schlangen, E. (author)
This work proposes a method for numerically investigating the fracture mechanism of cement paste at the microscale based on X-ray computed tomography and nanoindentation. For this purpose, greyscale level based digital microstructure was generated by X-ray microcomputed tomography with a resolution of 2 μm/voxel length. In addition,...
journal article 2019
document
Xu, Y. (author), Zhang, H. (author), Šavija, B. (author), Chaves Figueiredo, S. (author), Schlangen, E. (author)
A method is presented to model deformation and fracture behavior of 3D printed disordered lattice materials under uniaxial tensile load. A lattice model was used to predict crack pattern and load-displacement response of the printed lattice materials. To include the influence of typical layered structures of 3D printed materials in the...
journal article 2019
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Xu, Y. (author), Zhang, H. (author), Schlangen, E. (author), Lukovic, M. (author), Šavija, B. (author)
Auxetic behavior refers to material with negative Poisson's ratio. In this research, a new type of cementitious auxetic material is developed. A novel crack bridging auxetic mechanism is discovered which is in contrast with a local buckling mechanism commonly employed to trigger auxetic behavior. Taking advantage of 3D printing techniques,...
journal article 2020
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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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Chang, Z. (author), Zhang, Hongzhi (author), Schlangen, E. (author), Šavija, B. (author)
The lattice fracture model is a discrete model that can simulate the fracture process of cementitious materials. In this work, the Delft lattice fracture model is reviewed and utilized for fracture analysis. First, a systematic calibration procedure that relies on the combination of two uniaxial tensile tests is proposed to determine the input...
journal article 2020
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