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Found 6423 publications

Effect of Sugarcane Bagasse Ash on the sustainable performance of hot-mix asphalt: A case study of experimental and numerical analysis

Adeyemi Oluwaseun Adeboje Majid Movahedi Rad Udeme Udo Imoh Rauf Hassan Ebunlomo Ruth Adekola

Publication Name: Case Studies in Construction Materials

Publication Date: 2026-07-01

Volume: 24

Issue: Unknown

Page Range: Unknown

Description:

The growing demand for sustainable road infrastructure has intensified the interest in alternative mineral fillers that reduce natural resource consumption and environmental impacts. This study investigates the use of Sugarcane Bagasse Ash (SBA), an abundant agricultural by-product in sub-Saharan Africa, as a partial replacement for conventional mineral fillers in hot-mix asphalt (HMA). Unlike previous studies that considered SBA primarily as a minor additive, this study provides a systematic evaluation across a wide replacement range (0–16 %), combined with experimental testing and numerical validation. Marshall and indirect tensile strength (ITS) tests were conducted on HMA mixtures produced using locally sourced Nigerian aggregates and 60/70 penetration-grade bitumen. A three-dimensional finite element model (FEM) of the ITS configuration was developed to corroborate the experimental response and identify stress concentration zones. results indicate that SBA improves both mechanical and volumetric performance within an optimal replacement range of 6–10 %, with peak performance of approximately 8 % SBA. Within this range, Marshall stability increased from 7.6 kN to 9.0 kN, the Marshall quotient reached 3.3 kN/mm, bulk density increased to 2.51 g/cm³, and air voids decreased from 4.9 % to 3.5 %, remaining within standard design limits. Microstructural analyses confirmed the predominance of amorphous silica and porous SBA morphology, which promoted enhanced filler–binder interactions and mixture densification. FEM predictions of peak tensile stress agreed with laboratory ITS results within 10 % and successfully reproduced observed crack initiation zones. Excessive SBA content (> 10 %) led to reduced stability and density owing to over-filling effects. The findings demonstrate that 6–10 % SBA is a technically viable and sustainable filler replacement for HMA, particularly in sugarcane-producing regions, offering improved performance alongside waste valorization and reduced reliance on quarry-derived fillers.

Open Access: Yes

DOI: 10.1016/j.cscm.2026.e05769

On design method of lateral-torsional buckling of beams: State of the art and a new proposal for a general type design method

Bettina Badari F. Papp

Publication Name: Periodica Polytechnica Civil Engineering

Publication Date: 2015-01-01

Volume: 59

Issue: 2

Page Range: 179-192

Description:

After introducing the Eurocode standards several theses have been published on the now much-discussed phenomenon of lateral-torsional buckling of steel structural elements under pure bending. According that, researchers are working on the development of such new design methods which can solve the problems of the design formulae given by the EN 1993-1-1. This paper gives a detailed review on the proposals for novel hand calculation procedures for the prediction of LT buckling resistance of beams. Nowadays, the application of structural design softwares in practical engineering becomes more common and widespread. Recognizing this growing interest, the main objective of our research work is the development of a novel, computer-aided design method. In this paper the details of a general type stability design procedure for the determination of the LT buckling resistance of members under pure bending are introduced. Here, the theoretical basis of the proposed method is clarified, the calculation procedure is detailed and some results for the evaluation of the appropriateness of the method is also presented. Based on the evaluations it can be stated that the new, general type design method is properly accurate and has several advantages on the stability check of beams under bending.

Open Access: Yes

DOI: 10.3311/PPci.7837

Data-driven linear parameter-varying modelling of the steering dynamics of an autonomous car

Gábor Rödönyi R. Tóth Péter Korös Dániel Pup Ádám Kisari Zsombor Vigh József Bokor

Publication Name: IFAC Papersonline

Publication Date: 2021-07-01

Volume: 54

Issue: 8

Page Range: 20-26

Description:

Developing automatic driving solutions and driver support systems requires accurate vehicle specific models to describe and predict the associated motion dynamics of the vehicle. Despite of the mature understanding of ideal vehicle dynamics, which are inherently nonlinear, modern cars are equipped with a wide array of digital and mechatronic components that are difficult to model. Furthermore, due to manufacturing, each car has its personal motion characteristics which change over time. Hence, it is important to develop data-driven modelling methods that are capable to capture from data all relevant aspects of vehicle dynamics in a model that is directly utilisable for control. In this paper, we show how Linear Parameter-Varying (LPV) modelling and system identification can be applied to reliably capture personalised model of the steering system of an autonomous car based on measured data. Compared to other nonlinear identification techniques, the obtained LPV model is directly utilisable for powerful controller synthesis methods of the LPV framework.

Open Access: Yes

DOI: 10.1016/j.ifacol.2021.08.575

An economic prediction of the finer resolution level wavelet coefficients in electronic structure calculations

János Pipek Szilvia Nagy

Publication Name: Physical Chemistry Chemical Physics

Publication Date: 2015-01-01

Volume: 17

Issue: 47

Page Range: 31558-31565

Description:

In wavelet based electronic structure calculations, introducing a new, finer resolution level is usually an expensive task, this is why often a two-level approximation is used with very fine starting resolution level. This process results in large matrices to calculate with and a large number of coefficients to be stored. In our previous work we have developed an adaptively refined solution scheme that determines the indices, where the refined basis functions are to be included, and later a method for predicting the next, finer resolution coefficients in a very economic way. In the present contribution, we would like to determine whether the method can be applied for predicting not only the first, but also the other, higher resolution level coefficients. Also the energy expectation values of the predicted wave functions are studied, as well as the scaling behaviour of the coefficients in the fine resolution limit.

Open Access: Yes

DOI: 10.1039/c5cp01214g

Thermodynamic Processes in Nanostructured Thermocoatings

David Bozsaky

Publication Name: Current Topics and Trends on Durability of Building Materials and Components Proceedings of the 15th International Conference on Durability of Building Materials and Components Dbmc 2020

Publication Date: 2020-01-01

Volume: Unknown

Issue: Unknown

Page Range: 1127-1134

Description:

In the 21st century, global climate change and the high level of fossil energy consumption have introduced changes affecting all sectors of the economy, including the building industry. This process has prompted EU members to create strict regulations in building energetics. It has become a serious task for architects to find more effective ways for thermal insulation. One of these options is the application of nanostructured materials. Among them nano-ceramic thermocoatings open a wide range of research fields, because complete agreement had not been already found about their insulating effect. In order to explore and describe the thermodynamic process inside nano-ceramic thermocoatings 6 series of heat transfer resistance experiments were performed in 2014-2018. Several building structure configurations with 12 different orders of layers were tested with a standard heat flow meter. On basis of these results it could be concluded that in case of nano-structured thermocoatings convective heat transfer coefficient might be taken account in different way than in case of traditional macro-structured thermal insulation materials. Based on research results, the limits of its applicability can also be concluded. It has also been found that the insulating effect of nanostructured thermocoatings depends on the material characteristics of the insulated surface.

Open Access: Yes

DOI: 10.23967/dbmc.2020.139

Examination of the Tribological Mechanism of Various Ceramic Nanoparticles in an Oil-Based C60 Fullerene Solution

Igor Velkavrh Fevzi Kafexhiu I. Szabó

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 1057-1062

Description:

This study aims to evaluate the tribological mechanisms of CuO, SiO2, and Y2O3 ceramic nanoparticles in an oil-based C60 fullerene solution using experimental tribotests. The goal is to investigate the impact of these nanoparticles on friction and wear, offering insights into their potential for enhancing lubrication efficiency in automotive applications. Nanoparticles were homogenized using ethyl oleate surface modification. Testing involved a simplified ball-on-disc specimen in a linear oscillating configuration. Results show that the nanoparticles reduce dynamic friction by up to 10 % and static friction by 6 %. They reduce wear on test specimens by 45–81 %. CuO and SiO2 components are typically used for harder specimens, and Y2O3 nanoparticles for softer ones. Scanning electron microscopy identifies characteristic wear mechanisms, and energy-dispersive X-ray spectroscopy determines nanoparticle distribution on worn surfaces. The potential of nanoparticle additives in enhancing automotive lubrication and reducing friction and wear is highlighted, contributing to the industry's pursuit of efficiency and environmental sustainability.

Open Access: Yes

DOI: 10.3303/CET24114177

Development of Injection Moulded Electromagnetic Pulse Shielded Polymer Cover

Ferenc Ronkay Gabor Dogossy

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 186-193

Description:

Technology for an electromagnetic pulse shielded injection moulded product was developed, using in-mould metal mesh and a 3D printed spacer made of the same type of acrylonitrile-butadiene-styrene as the injection moulded polymer. The functional and mechanical properties of the manufactured flat and dumbbel specimens were tested. The metal mesh increased the stiffness of the plastic, decreased its Charpy impact strength, and did not significantly affect its tensile strength. Computed tomography scans confirmed that delamination and microcracking occur during the failure due to different elongation of the plastic and metal. The attenuation at 1 GHz was 16-19 dB, depending on the metal mesh used. The shielding properties were affected by the fact that the high pressure at the mould filling during the injection moulding process distorted the geometry of the metal mesh.

Open Access: Yes

DOI: 10.3233/ATDE240544

Image-Based Estimation of Porosity and Tortuosity in Fibrous Acoustic Absorbers

Krisztián Horváth Attila Schweighardt Krisztián Horváth Krisztián Horváth

Publication Name: Engineering Reports

Publication Date: 2025-12-01

Volume: 7

Issue: 12

Page Range: Unknown

Description:

This study presents a fast and non-destructive image-based method for estimating two key acoustic parameters—open porosity and tortuosity—in fibrous sound-absorbing materials. The approach uses a single grayscale optical micrograph, which is down-sampled, contrast-equalized, and segmented via adaptive thresholding. From the resulting binary fiber mask, two geometric descriptors are extracted: coverage and a one-pixel-wide skeleton. Porosity is estimated using a simple linear formula calibrated on three reference materials, yielding an average absolute error below 0.3% when compared with argon gas pycnometry. Tortuosity is inferred from the total skeleton length relative to the image area, producing a stable ranking across materials with consistent bias relative to measured data. Additionally, a random forest model using only three image features—coverage, median fiber radius, and skeleton length—predicts airflow resistivity with over 70% explained variance. The full analysis pipeline is implemented in Python using open-source libraries (OpenCV, scikit-image) and runs in under half a second per image on standard hardware. This makes the method well suited for early-stage material screening, in-line quality control, or laboratory support, without the need for destructive testing or costly instruments. The approach bridges the gap between optical imaging and physical parameter estimation, offering a lightweight alternative to traditional porosity and impedance-tube measurements.

Open Access: Yes

DOI: 10.1002/eng2.70537

Analysing the Environmental Durability and Chrysotile Content of Asbestos Cement Products by FT-IR Spectroscopy

András Torma Gergely Zoltán Macher Dóra Beke

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 709-714

Description:

The aim of this paper is to examine the environmental resistance and chrysotile content of different asbestos cement products and to prove the relationship between these two factors by analytical results. The paper includes Fourier-transform infrared (FT-IR) spectroscopic analysis of asbestos cement pipes and asbestos cement products with corrugated and flat characteristics. The methodology of the study is based on FT-IR spectroscopy and general statistical approaches, and the results obtained are compared using correlation analysis. The background to the topic is that asbestos cement products are still widely used today despite their harmful effects on health, contrary to European Union asbestos-free targets. A damaged and eroded asbestos cement product loses several grams of asbestos and cement per year from its matrix structure, which is exacerbated by exposure to various environmental influences. The match rate of the chrysotile spectrum for analysed samples has been over 50 % in each case. In the number of measurements, the chrysotile detection rate was 7.64 % higher for degraded and eroded samples. In addition, in the samples exposed to environmental factors, the percentage variance was approximately 10 % or higher, with the exception of asbestos cement pipes. The results provide a basis for situational awareness options. Analytic practitioners, material science researchers, and analysts can use them.

Open Access: Yes

DOI: 10.3303/CET24114119