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Experimentally informed modeling of the early-age stress evolution in cementitious materials using exponential conversion from creep to relaxation

Liang, M. (author), Luzio, Giovanni Di (author), Schlangen, E. (author), Šavija, B. (author)

This study presents comprehensive numerical modeling methods for simulating early-age stress (EAS) relaxation in cementitious materials, based on the autogenous deformation (AD), elastic modulus, creep, and stress continuously tested by a mini temperature stress testing machine (Mini-TSTM) and a mini AD testing machine from a very early age ...

journal article 2024

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Autogenous deformation-induced stress evolution in cementitious materials considering viscoelastic properties: A review of experiments and models

Liang, M. (author), Xie, J. (author), He, S. (author), Chen, Y. (author), Schlangen, E. (author), Šavija, B. (author)

Early-age cracking risk induced by autogenous deformation is high for cementitious materials of low water-binder ratios. The autogenous deformation, viscoelastic properties, and stress evolution are three important factors for understanding and quantifying the early-age cracking risk. This paper systematically reviewed the experimental and...

review 2024

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Two scale models for fracture behaviours of cementitious materials subjected to static and cyclic loadings

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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Effects of temperature on autogenous deformation and early-age stress evolution in cement pastes with low water to cement ratio

Liang, M. (author), Liu, C. (author), Liang, X. (author), Chang, Z. (author), Schlangen, E. (author), Šavija, B. (author)

This paper investigates the influence of temperature on autogenous deformation and early-age stress (EAS) evolution in ordinary Portland cement paste using a recently developed Mini Temperature Stress Testing Machine (Mini-TSTM) and Mini Autogenous Deformation Testing Machine (Mini-ADTM). In the Mini-TSTM/ ADTM, CEM I 42.5 N paste with a...

journal article 2023

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On the chemo-mechanical evolution process of high-volume slag cement paste

Liang, M. (author), Zhang, Y. (author), He, S. (author), Chen, Y. (author), Schlangen, E. (author), Šavija, B. (author)

This study investigated the evolution process of high-volume slag cement (HVSC) paste from a chemo-mechanical standpoint. HVSC specimens with a 70 w.t. % slag replacement rate were studied at various ages. Evolution of phase assemblage, microstructure development, and micromechanical properties were analyzed using TGA/XRD/MIP/SEM-EDS and nano...

journal article 2023

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Predicting micromechanical properties of cement paste from backscattered electron (BSE) images by computer vision

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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Lattice modelling of early-age creep of 3D printed segments with the consideration of stress history

Chang, Z. (author), Liang, M. (author), He, S. (author), Schlangen, E. (author), Šavija, B. (author)

We propose a new numerical method to analyze the early-age creep of 3D printed segments with the consideration of stress history. The integral creep strain evaluation formula is first expressed in a summation form using superposition principle. The experimentally derived creep compliance surface is then employed to calculate the creep strain...

journal article 2023

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Does early age creep influence buildability of 3D printed concrete? Insights from numerical simulations

Chang, Z. (author), Liang, M. (author), Chen, Y. (author), Schlangen, E. (author), Šavija, B. (author)

Cementitious materials may exhibit significant creep at very early age. This is potentially important for concrete 3D printing, where the material is progressively loaded even before it sets. However, does creep actually affect the buildability of 3D printed concrete? Herein, the influence of early-age creep on the buildability of 3D printed...

journal article 2023

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Autogenous deformation induced- stress evolution in high-volume GGBFS concrete: Macro-scale behavior and micro-scale origin

Liang, M. (author), Chang, Z. (author), Zhang, Y. (author), Cheng, H. (author), He, S. (author), Schlangen, E. (author), Šavija, B. (author)

This study aims to experimentally investigate the autogenous deformation and the stress evolution in restrained high-volume ground granulated blast furnace slag (GGBFS) concrete. The Temperature Stress Testing Machine (TSTM) and Autogenous Deformation Testing Machine (ADTM) were used to study the macro-scale autogenous deformation and stress...

journal article 2023

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Can superabsorbent polymers be used as rheology modifiers for cementitious materials in the context of 3D concrete printing?

Chen, Y. (author), Liang, M. (author), Zhang, Y. (author), Li, Z. (author), Šavija, B. (author), Schlangen, E. (author), Copuroglu, Oguzhan (author)

Autogenous shrinkage may be a critical issue concerning the use of limestone-calcined clay-cement (LC3) in high-performance concrete and 3D printable cementitious materials, which have relatively low water to binder (W/B) ratio. Adding an internal curing agent, i.e., superabsorbent polymer (SAP), could be a viable solution in this context....

journal article 2023

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Early-age creep of 3D printable mortar: Experiments and analytical modelling

Chang, Z. (author), Liang, M. (author), Xu, Y. (author), Wan, Z. (author), Schlangen, E. (author), Šavija, B. (author)

In this study, an experimental setup to characterize the early-age creep of 3D printable mortar was proposed. The testing protocol comprises quasi-static compressive loading-unloading cycles, with 180-s holding periods in between. An analytical model based on a double power law was used to predict creep compliance with hardening time and...

journal article 2023

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Bayesian Inverse Modelling of Early-Age Stress Evolution in GGBFS Concrete Due to Autogenous Deformation and Aging Creep

Liang, M. (author), Schlangen, E. (author), Šavija, B. (author)

Stress evolution of restrained concrete is directly related to early-age cracking (EAC) potential of concrete, which is a tricky problem that often happens in engineering practice. Due to the global objective of carbon reduction, Ground granulated blast furnace slag (GGBFS) concrete has become a more promising binder comparing with Ordinary...

book chapter 2023

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Microstructure-informed deep convolutional neural network for predicting short-term creep modulus of cement paste

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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Stress evolution in restrained GGBFS concrete due to autogenous deformation: bayesian optimization of aging creep

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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Interpretable Ensemble-Machine-Learning models for predicting creep behavior of concrete

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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Predicting early-age stress evolution in restrained concrete by thermo-chemo-mechanical model and active ensemble learning

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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Numerical simulation of elastic buckling in 3D concrete printing using the lattice model with geometric nonlinearity

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

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The Influence of Autogenous Shrinkage and Creep on the Risk of Early Age Cracking

Schlangen, E. (author), Liang, M. (author), Šavija, B. (author)

The study aims to investigate the mechanism of early-age cracks in different massive concrete structures (i.e. tunnels, bridge foundations and underground parking garages), with the objective of answering the following three specific questions: <br/><br/>1) How does the parameters of concrete proportion mix (e.g. w/c ratio, cementitious...

book chapter 2022

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Flexural strength and fatigue properties of interfacial transition zone at the microscale

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 μm³) 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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3D concrete printing: Lattice modeling of structural failure considering damage and deformed geometry

Chang, Z. (author), Liang, M. (author), Xu, Y. (author), Schlangen, E. (author), Šavija, B. (author)

This research studies the impact of localized damage and deformed printing geometry on the structural failure of plastic collapse for 3D concrete printing (3DCP) using the lattice model. Two different approaches are utilized for buildability quantification: the (previously developed) load-unload method, which updates and relaxes the printing...

journal article 2022