Journal: Construction and Building Materials

Abbreviation

Constr. Build. Mater.

Publisher

Elsevier

Journal Volumes

ISSN

0950-0618

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Publications1 - 10 of 115
  • Mechanical behaviour of bitumen emulsion-cement composites across the structural transition of the co-binder system
    Item type: Journal Article
    Miljković, Miomir; Poulikakos, Lily D.; Piemontese, Fabio; et al. (2019)
    Construction and Building Materials
  • Experimental assessment and modelling of effective tensile elastic modulus in high performance concrete at early age
    Item type: Journal Article
    Dabarera, Arosha; Li, Liang; Lura, Pietro; et al. (2022)
    Construction and Building Materials
    This paper focuses on the age-adjusted effective elastic modulus (Eₐ(t,t₀)) in high performance concrete subjected to sustained tensile loading conditions at early age. First, the existing approaches to determining Eₐ(t,t₀) are discussed, underlining their limitations. Second, a novel experimental approach is put forward to capture Eₐ(t,t₀) using an advanced Temperature Stress Testing Machine and a unique direct tensile test setup. In this approach, both pure elastic modulus (E(t)) and Eₐ(t,t₀) can be directly measured, whereas, in existing methods, the predictions are based on empirically determined values/models of ageing and creep coefficients. A unique set of test data obtained based on the proposed approach is presented to assess the early-age evolution of Eₐ(t,t₀) and its key influencing factors. Such obtained experimental values are used to compute the evolutions of the reduction factors (k(t,t₀)) simply by obtaining the ratio between experimentally determined values of E(t) and Eₐ(t,t₀). The applicability of existing approaches for predicting k(t,t₀) is evaluated, and the causes for discrepancies between experimental values and predictions are discussed. Finally, an empirical model is proposed in this paper to quantify the k(t,t₀) profiles. It is shown that the proposed model is convenient, easily adaptable for different types of concrete without the need for an extensive test database, and yet realistically reflects the nonlinearity of k(t,t₀) profiles at early ages.
  • Rotational mechanical behaviour of wood-wood connections with application to double-layered folded timber-plate structure
    Item type: Journal Article
    Gamerro, Julien; Robeller, Christopher; Weinand, Yves (2018)
    Construction and Building Materials
  • Prediction and deployment of compressive strength of high-performance concrete using ensemble learning techniques
    Item type: Journal Article
    Taiwo, Ridwan; Yussif, Abdul-Mugis; Adegoke, Adesola Habeeb; et al. (2024)
    Construction and Building Materials
    Concrete is widely utilized in construction; however, accurately predicting its compressive strength is difficult due to the complex relationships within its mixture. Although previous studies have predicted the compressive strength of high-performance concrete (HPC), the literature lacks an optimized end-to-end framework for this purpose. To address this gap, this study conducts four experiments focusing on various stages of the predictive modeling process. Experiment 1 proposes and evaluates ensemble models using voting and stacking techniques and benchmarks them against eight other models. The experiment also investigates the impact of different data-splitting ratios on model performance. In experiment 2, these models are ranked based on ten evaluation metrics using the ELimination Et Choix Traduisant la REalité (ELECTRE) method. Experiment 3 involves selecting the best features for model retraining using Recursive Feature Elimination (RFE) to enhance predictive accuracy and efficiency. In experiment 4, the interpretability of the selected model is investigated using intrinsic and extrinsic methods. The results demonstrate that data splitting ratios influence model performance, as the ensemble stacking regressor using 30 % of the data for testing (ESR-30) outperforms other models. RFE improves the model's performance, reducing the root mean square error (RMSE) from 4.136 to 3.928 by 5.0 %, increasing the coefficient of determination (R2) from 0.937 to 0.943, and reducing the computational time by 30.8 %. Intrinsic feature importance and SHapley Additive exPlanations (SHAP) values identify age of testing and cement content as the most critical features influencing compressive strength predictions. The optimized model is deployed as a web-based application, providing a user-friendly interface for predicting HPC compressive strength. This study has significant implications for improving the reliability, efficiency, and accessibility of concrete compressive strength predictions in the construction industry.
  • Use of eggshell waste: A green and effective method for the synthesis of pure calcium hydroxide suspensions
    Item type: Journal Article
    Lanzón, Marcos; Madrid-Mendoza, Juan A.; Navarro-Moreno, David; et al. (2023)
    Construction and Building Materials
    This paper presents a rapid method to obtain pure suspensions of Ca(OH)2 dispersed in 2-propanol. To this aim eggshell wastes (CaCO3) were decarbonated to calcium oxide (CaO) followed by sonication-assisted hydrolysis in water/2-propanol to form calcium hydroxide (Ca(OH)2). An important advantage of the method is that it does not require chemical reagents due to the high purity of eggshell in CaCO3. Moreover, CaO is fully converted into Ca(OH)2 which means that purification steps are not needed, as occurs in conventional routes of synthesis. To assess the reliability of the synthetic procedure, the purity and amount of Ca(OH)2 were studied by X-ray diffraction (XRD), infrared spectroscopy (FTIR) and thermal analysis (TG). In addition, the morphology and crystallite size were examined by transmission electron microscopy (TEM) and X-ray diffraction (XRD) using Rietveld refinement method. It was found that sonicated Ca(OH)2 suspensions (5 g/L) were composed of particles that ranged in size from several nanometers to few micrometers. Finally, the suitability of Ca(OH)2 from eggshell to reinforce architectural stone was also studied by microscopy examination, colour change tests, surface hardness and surface erosion measurements. All tests confirmed the consolidation effectiveness was comparable to conventional nanolime treatments and surface erosion was visibly reduced.
  • A computational study of the effect of structural anisotropy of porous asphalt on hydraulic conductivity
    Item type: Journal Article
    Gruber, I.; Zinovik, I.; Holzer, L.; et al. (2012)
    Construction and Building Materials
  • Experimental push-out investigation on the in-plane force-deformation behavior of integrally-attached timber Through-Tenon joints
    Item type: Journal Article
    Rezaei Rad, Aryan; Weinand, Yves; Burton, Henry (2019)
    Construction and Building Materials
  • High-performance timber-concrete-composites with polymer concrete and beech wood
    Item type: Journal Article
    Stucki, Sandro; Kelch, Steffen; Mamie, Tim; et al. (2024)
    Construction and Building Materials
    The performance of adhesive-bonded timber-concrete-composites (TCC) can be enhanced by using beech wood and polymer concrete (PC). In this work, two different PCs with an epoxy- and a polyurethane (PUR)-based matrix were investigated for application in TCCs. The mechanical performances were tested in dry and wet state by small-scale shear tests and flexural tests. Epoxy-PC showed high bond strength to beech with a shear strength of 16.7 ± 3.0 MPa compared to 3.2 ± 1.7 MPa observed with PUR-PC. Characterization of the swelling strain with digital image correlation (DIC) showed superior water stability of the epoxy-PC compared to PUR-PC. The results indicate that PCs, especially epoxy-PC, could be viable replacements for cement-based concrete in TCCs.
  • Analysis of waste polyethylene (PE) and its by-products in asphalt binder
    Item type: Journal Article
    Kakar, Muhammad R.; Mikhailenko, Peter; Piao, Zhengyin; et al. (2021)
    Construction and Building Materials
    The use of waste plastics in partial asphalt binder replacement and substitute for polymer modification has the potential to contribute to the sustainability of road infrastructure as well as preservation of natural resources. In this study, two types of polyethylene (PE) waste plastics PE-pellets and PE-shreds (a by-product of the former, currently incinerated after production) were blended with a conventional asphalt binder in order to analyze their effect on the chemo-mechanical and thermal behavior. Particular attention was paid to the characterization of the waste PE as well as to the description of sample preparation, lacking in other studies. Differential Scanning Calorimetry (DSC), Thermal Gravimetric Analysis (TGA), Fourier Transform Infrared (FTIR) spectroscopy and Environmental Scanning Electron Microscopy (ESEM) were used to assess the different types of PE and blended asphalt binder's thermal properties, chemical modification degree and quality of blending, respectively. The rheological performance of waste PE blended binder was obtained using the Dynamic Shear Rheometer (DSR). The results illustrated that compared to commercial polymer modified binders, the binder resistance against high temperature distresses such as rutting could improve substantially with adding waste PE. The modulus of the binders at low temperatures was comparable. However, the negative results of high temperature storage stability of the PE blended binders indicated that attention needs to be paid to the mixture preparation method.
  • Acoustic emission for monitoring a reinforced concrete beam subject to four-point-bending
    Item type: Journal Article
    Schechinger, Barbara; Vogel, Thomas (2007)
    Construction and Building Materials
Publications1 - 10 of 115