- document
-
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
- document
-
Zhang, Shizhe (author), He, S. (author), Ghiassi, Bahman (author), van Breugel, K. (author), Ye, G. (author)This paper presents an experimental study on the interface bonding properties of polyvinyl alcohol (PVA) fiber in alkali-activated slag/fly ash (AASF) pastes. Three interface bonding properties (i.e., the chemical bonding energy Gd, the initial frictional bond strength τ0, and slip-hardening behavior) were determined using single-fiber pullout...journal article 2023
- document
-
Li, Z. (author), Liang, X. (author), Liu, C. (author), Liang, M. (author), van Breugel, K. (author), Ye, G. (author)This study investigates the deformation of free and stress of restrained alkali-activated slag concrete (AASC), respectively, under semi-adiabatic condition. The concrete shows first thermal expansion, which is compensated soon by autogenous shrinkage. The subsequent cooling down of the concrete aggravates shrinkage and development of tensile...journal article 2022
- document
-
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
- 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
-
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 (>80%) even subjected to very high stress levels....journal article 2021
- 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
-
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
- document
-
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
- document
-
Lu, T. (author), Li, Z. (author), van Breugel, K. (author)In recent decades, several simulation models have been proposed to predict autogenous shrinkage of cementitious systems. In most of these models, however, only the elastic deformation caused by self-desiccation of the hydrating cement paste is considered. In fact, cement paste is not an ideal elastic material. Also the time-dependent...journal article 2020
- document
-
van Breugel, K. (author)The world’s infrastructure is vital for providing accommodation and mobility for people. Although it is obvious that the construction industry has been crucial for realizing building and civil infrastructures, it is also clear that building activities have a big impact on the environment. Still growing and developing societies and economies...journal article 2019
- document
-
Agar Ozbek, Ayda Safak (author), Pedersen, Ronnie Refstrup (author), Weerheijm, J. (author), van Breugel, K. (author)This study presents the numerical analyses conducted to investigate the impact behavior of different porous concretes, which have also been cast and tested experimentally. For a realistic representation of the real porous concretes containing arbitrary shaped air pores, a mesh generation code was developed in which the aggregates in the...journal article 2019
- document
-
Agar Ozbek, Ayda Safak (author), Weerheijm, J. (author), van Breugel, K. (author)In this work, findings of a numerical study performed to investigate the impact behavior of porous concrete, modeled as a four phase cementitious composite consisting of aggregates, cement paste, interfacial transition zones (ITZ) and air, are presented. The numerical analyses contributed to the process of designing a special type of concrete...journal article 2019
- document
-
Pargar, F. (author), Koleva, D.A. (author), van Breugel, K. (author)In this paper the potentiometric response of a Ag/AgCl electrode as a chloride sensor in cementitious materials of different mix design was studied. The chloride sensor’s response was discussed with respect to the presence of hydration products around the sensor. The free chloride content inferred from the sensor’s response was compared to the...journal article 2019
- document
-
Pargar, F. (author), Kolev, H (author), Koleva, D.A. (author), van Breugel, K. (author)The stability and reproducibility of an Ag/AgCl sensors’ response in an alkaline medium are important for the application of these sensors in cementitious materials. The sensors’ response, or their open circuit potential (OCP), reflects a dynamic equilibrium at the sensor/environment interface. The OCP response in an alkaline medium is affected...journal article 2018
- document
-
Nedeljković, Marija (author), Lukovic, M. (author), van Breugel, K. (author), Hordijk, D.A. (author), Ye, G. (author)This paper presents a development of a ductile alkali-activated fly ash (FA) and ground granulated blast furnace slag (GBFS) based composite as an environmentally friendly material for structural concrete application. For this purpose, polyvinyl alcohol (PVA) fibres and sand aggregate were combined with alkali-activated paste. Workability,...journal article 2018
- document
-
Pargar, F. (author), Kolev, H (author), Koleva, D.A. (author), van Breugel, K. (author)Characterization of the Ag/AgCl electrode is a necessary step toward its<br/>application as a chloride sensor in a highly alkaline medium, such as concrete.<br/>The nucleation and growth of AgCl on Ag in 0.1 M HCl was verified through<br/>cyclic voltammetry. Ag anodization was performed at current densities, determined<br/>by potentiodynamic...journal article 2018
- document
-
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
- document
-
van Breugel, K. (author)Models play a vital role in science and technology and in the evolution of modern societies. They are used for describing processes and mechanisms, experimental observations, analyses and predictions. In spite of the fact that models are a reduction of reality, the achievements of modern societies are impressive and would have been...journal article 2018