Searched for: +
(1 - 20 of 59)

Pages

document
Zhang, H. (author), Schlangen, E. (author), Ge, Z. (author), Šavija, B. (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 behaviour. This paper presents an experimentally informed approach for modelling elastic and transport properties of cement...
conference paper 2021
document
Rossi, Emanuele (author), Zhang, Hongzhi (author), Çopuroğlu, Oğuzhan (author), Polder, Rob B. (author), Šavija, Branko (author), Nijland, Timo G. (author)
An important input parameter for numerical models that simulate cracking of the concrete cover due to reinforcement corrosion is the Elastic modulus of corrosion product (Ecp). Despite its relevance, Ecp is subject of significant variations according to the values reported in the literature, which vary from less than 100 MPa up to 360 GPa....
conference paper 2021
document
Rossi, E. (author), Zhang, Hongzhi (author), Nijland, Timo G. (author), Copuroglu, Oguzhan (author), Polder, R.B. (author), Šavija, B. (author)
An important input parameter for numerical models that simulate cracking of the concrete cover due to reinforcement corrosion is the Elastic modulus of corrosion product (Ecp). Despite its relevance, Ecp is subject of significant variations according to the values reported in the literature, which vary from less than 100 MPa up to 360 GPa....
conference paper 2021
document
Zhang, H. (author), Schlangen, E. (author), Ge, Zhi (author), Šavija, B. (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 behaviour. This paper presents an experimentally informed approach for modelling elastic and transport properties of cement...
conference paper 2021
document
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
document
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
document
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
document
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
document
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
document
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
document
Jiang, Nengdong (author), Ge, Zhi (author), Guan, Yanhua (author), Zuo, Zhiwu (author), Zhang, Hongzhi (author), Ling, Yifeng (author), Šavija, B. (author)
This work presents a study of mechanical properties of foamed concrete at the meso-scale based on a combination of X-ray computed tomography (XCT) technique and a discrete lattice type fracture model. The microstructure of the foamed concrete with different densities was obtained by XCT technique and binarized as two-phase (pore/solid) materials...
journal article 2022
document
Tawfek, Abdullah M. (author), Ge, Zhi (author), Yuan, Huaqiang (author), Zhang, Ning (author), Zhang, Hongzhi (author), Ling, Yifeng (author), Guan, Yanhua (author), Šavija, B. (author)
The mechanical performance of engineered cementitious composite (ECC) depends greatly on fiber orientation and distribution. In this paper, the effect of fiber orientation on ECC's mechanical properties was investigated using two different casting methods: a flow-induced casting was used to enhance the fiber orientation within ECC mixture and...
journal article 2023
document
Zhang, Cheng-lin (author), Chen, Wei-kang (author), Mu, Song (author), Šavija, B. (author), Liu, Qing-feng (author)
Reinforced concrete (RC) structures may suffer from serious durability problems during long-term service. To investigate the deterioration of RC structures subjected to the dual attacks of chlorides and sulfates, this study proposes a coupled model for external sulfate attack (ESA) and its effect on chloride binding and diffusion. To account for...
journal article 2021
document
Zhang, Hongzhi (author), Yuan, Huaqiang (author), Ge, Zhi (author), Wu, Jiajie (author), Fang, Cheng (author), Schlangen, E. (author), Šavija, B. (author)
Clay brick is one of the major components of demolition waste, which is generally landfilled. Effective and new uses of recycled clay brick may provide sustainability benefits in terms of landfill reduction. Therefore, this research aims at applying Recycled fine clay brick aggregates (RFCBA) with sizes from 0.075 mm–4.75 mm to prepare Self...
journal article 2021
document
Zhu, Xuezhen (author), Zhang, Minghu (author), Shi, Jinyan (author), Weng, Yiwei (author), Yalçınkaya, Çağlar (author), Šavija, B. (author)
High-strength engineered cementitious composites (ECC) typically require higher cement content, which is negative from the sustainability point of view. To alleviate this problem, herein a low-cost and eco-friendly high-strength ECC (with a compressive strength of over 100 MPa) was developed, and diatomite was used to replace a small amount...
journal article 2024
document
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
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
document
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
document
Zhang, Hongzhi (author), Shao, Yingxuan (author), Zhang, Ning (author), Tawfek, Abdullah M. (author), Guan, Yanhua (author), Sun, Renjuan (author), Tian, Changjin (author), Šavija, B. (author)
Engineered cementitious composites (ECCs) belong to a broad class of fibre-reinforced concrete. They incorporate synthetic polyvinyl alcohol (PVA) fibres, cement, fly ash and fine aggregates, and are designed to have a tensile strain capacity typically beyond 3%. This paper presents an investigation on the carbonation behaviour of engineered...
journal article 2022
document
Chang, Z. (author), Zhang, Hongzhi (author), Liang, M. (author), Schlangen, E. (author), Šavija, B. (author)
This paper explores buildability quantification of randomly meshed 3D printed concrete objects by considering structural failure by elastic buckling. The newly proposed model considers the most relevant printing parameters, including time-dependent material behaviors, printing velocity, localized damage and influence of sequential printing...
journal article 2022
Searched for: +
(1 - 20 of 59)

Pages