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1.
The potential for EVITA project e-KPIs to be used by Road Authorities
Darko Kokot, 2021, objavljeni znanstveni prispevek na konferenci

Povzetek: Planning different strategies in road maintenance is one of the most important activities inroad asset management. Assessment of different strategies and their comparison can be done by implementing an appropriate measure - Key Performance Indicators (KPIs). KPIs are currently used in many Road Authorities, and systematic research on the subject and development of indicators has been ongoing for many years. The Conference of European Directors of Roads (CEDR) funded project “EVITA - Environmental Performance Indicators for the Total Road Infrastructure Assets” aimed at developing and integrating new and existing environ-mental KPIs (e-KPIs) into the asset management process, taking into account the expectations of different stakeholders (users, operators, residents, etc.). The research focus was on environmental areas: Noise, with KPIs on day-evening-night & night noise, exposed population, population with sleep disturbance; Air, with KPIs on CO2, NOx, NO2 and PM10 emissions; Water, with KPIs on water quality and salting of roads; and Natural resources and GHG emissions, with KPIs on resource consumption and CO2e calculation. The project outputs were a set of e-KPIs produced after a comprehensive investigation of the state of the art during the project. The main benefit of this project is therefore to provide an applicable solution for the environmental assessment of different road infrastructure assets and to describe the expectations of different stakeholders in form of objective indicators. The ‘User Evaluation Trial’ phase of the project was used to gather feedback on the potential of e-KPIs to be used by national Road Authorities across Europe. Two Slovenian Road Authorities and one each from Denmark and Sweden were involved. The Slovenian Authorities provided input data for case studies, while all evaluated the proposed e-KPIs from their own perspective, taking into account national conditions and specificities.
Ključne besede: EVITA, environmental performance indicator, users’ feedback, stakeholder’ expectations
Objavljeno v DiRROS: 22.02.2024; Ogledov: 1; Prenosov: 1
.pdf Celotno besedilo (658,05 KB)
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2.
CoDEC : connected data for road infrastructure asset management
Sukalpa Biswas, Jacques Proust, Tadas Andriejauskas, Alex Wright, Carl van Geem, Darko Kokot, António Antunes, Vânia Marecos, José Barateiro, Shubham Bhusari, Uros Jovanovic, 2021, objavljeni znanstveni prispevek na konferenci

Povzetek: Road infrastructure asset management is rapidly transforming into a digital environment where data accessibility, effective integration and collaboration and accessibility from different sources and assets are key. However, current asset management processes are not yet fully integrated or linked, and there are incompatibilities between various systems and platforms that limit the ability to integrate asset management with BIM. The CoDEC project has sought to understand the current status of information management for assets, including inventory, condition and new data sources such as sensors and scanning systems, to identify the challenges and needs for linking and integrating different data sets to support effective asset management. As a result, CoDEC has developed a data dictionary framework to help link/integrate static and dynamic data for the "key" infrastructure assets (road pavements, bridges, tunnels). This will enable BIM and Asset Management Systems (AMS) to exchange data and help optimise and integrate data management across systems and throughout the different asset lifecycle phases, from build to operation. This work will be followed up with three pilot projects to demonstrate the feasibility of integrating asset data from various sources through linked data/semantic web technology to build the connection between AMS and BIM platforms.
Ključne besede: CoDEC, asset managemen, asset data, data dictionary, linked data, BIM, ontology
Objavljeno v DiRROS: 22.02.2024; Ogledov: 2; Prenosov: 1
.pdf Celotno besedilo (1,39 MB)
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3.
Volumetric view on asphalt mixture
Marjan Tušar, Mojca Ravnikar Turk, Lidija Ržek, 2023, objavljeni znanstveni prispevek na konferenci

Povzetek: An asphalt layer consists of stone aggregates, binder and air voids. The content of air voids (Vmin and Vmax), the voids filled with bitumen (VFBmin and VFBmax), the content of air voids in stone aggregates (VMAmin and VMAmax) and volume content of bitumen (VBmin) should be determined for each type of asphalt mixture. The volumetric properties of asphalt layer listed above are important parameters for assessing the properties of asphalt and are usually first presented in the requirements for produced asphalt mixtures and built in asphalt layers. Visualization of volumetric properties is important for understanding the composition of the produced asphalt mixture. The most appropriate is a triangular representation of the volumetric requirements for three main components of asphalt layer (stone, bitumen and air).
Ključne besede: volumetric representation, asphalt mixture, void content, voids in aggregate
Objavljeno v DiRROS: 22.02.2024; Ogledov: 1; Prenosov: 1
.pdf Celotno besedilo (715,71 KB)
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4.
Rheological behaviors of waste polyethylene modified asphalt binder : Statistical analysis of interlaboratory testing results
Di Wang, Andrea Baliello, Gustavo Pinheiro, Lily D. Poulikakos, Marjan Tušar, Kamilla Vasconcelos, Muhammad Rafiq Kakar, Laurent Porot, Emiliano Pasquini, Gaspare Giancontieri, Chiara Riccardi, Marco Pasetto, Davide Lo Presti, Augusto Cannone Falchetto, 2023, izvirni znanstveni članek

Povzetek: This article investigated the effect of waste polyethylene (PE) on the modified asphalt binders’ rheological behavior from a statistical point of view. The interlaboratory testing results from the RILEM Technical Committee 279 Valorization of Waste and Secondary Materials for Roads Task Group 1 were used for this purpose. First, an unaged 70/100 penetration graded neat binder was selected as the reference material. Next, a single 5 % content of waste PE additives (PE-pellets and PE-shreds) was mixed with a 95 % neat binder to prepare two PE modified binders. Then, dynamic shear rheometer–based temperature-frequency sweep tests were performed over a wide range of temperatures and frequencies to evaluate the rheological properties of these three binders. Different rheological behaviors were observed in the isochronal plots at high temperatures. Based on a reproducibility precision requirement proposed for phase angle, 28°C was set as the transition temperature across the rheological behaviors. Next, according to the three rheological behaviors defined in a previous study by the authors, statistical analysis was introduced to identify sensitive rheological parameters and determine the thresholds. Results indicate that the phase angle measured above 28°C and 1.59 Hz can be used as a sensitive parameter to discriminate the three rheological behaviors of PE modified binders. The thresholds among different behaviors were also calculated as an example for phase angle measured at the highest common testing temperature of 70°C. Additional experimental evaluations on more types of PE modified binders, especially at intermediate and high temperatures, are recommended to better understand their influence on the rheological behavior of PE modified binders.
Ključne besede: bitumen, polietilen, reologija, medlaboratorijska primerjava
Objavljeno v DiRROS: 20.02.2024; Ogledov: 17; Prenosov: 8
.pdf Celotno besedilo (1,19 MB)
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5.
SBA-15 mesoporous particles with adsorbed cresol red dye and functionalized with 3-aminopropyl groups : materials properties and dye release studies
Erika Švara Fabjan, Romana Cerc Korošec, Klara Šifrer, Andrijana Sever Škapin, Ramon Martinez Manez, 2024, izvirni znanstveni članek

Povzetek: Research in the field of sensing has focused on tailoring the responsiveness of materials through the variation in materials properties achieved via functionalization of the mesoporous matrix. pH indicator dyes capable of protonation/deprotonation reactions are known to display different forms, resulting in changes in colour. This research focused on the preparation of mesoporous substrates SBA-15 with integrated pH indicator dye o-cresolsulphonephtalein (cresol red) grafted with (3-aminopropy) trimethoxysilane (gaining functionalized-SBA-15 material) in order to gain a colour change response following release of the dye. UV-Vis reflectance and absorbance spectra were used to evaluate forms of cresol red. The textural properties, including specific surface area, pore size distribution and pore volume were evaluated using nitrogen sorption, and XRD analysis was conducted to evaluate crystallinity of the material and pore ordering. The presence of 3-aminopropyl groups was determined by thermal decomposition using TGA–DSC/MS. The functionalized SBA-15 materials loaded with cresol red mostly retained ordering of the pores and showed a slight reduction in surface area. Functionalization changed the surface properties of the material. In the non-functionalized SBA-15, cresol red was present in both double (H2L) and single (HL−) protonated forms, whereas in the functionalized SBA-15 the deprotonated L2−form prevailed. Through desorption experiments cresol red was successfully desorbed from selected sample to different media. The change of colour caused by alterations in the form of the dye once released from the mesoporous silica material into the medium was confirmed. The form of cresol red released was determined by the pH of the medium.
Ključne besede: mezoporozni materiali, SBA-15, funkcionalizacija, uravnavanje odzivnosti, zaznavanje
Objavljeno v DiRROS: 13.02.2024; Ogledov: 63; Prenosov: 39
.pdf Celotno besedilo (10,52 MB)
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6.
Effect of demineralization and ball milling treatments on the properties of Arundo donax and olive stone-derived biochar
Mariem Zouari, Laetitia Sarah Jennifer Marrot, David Brian DeVallance, 2024, izvirni znanstveni članek

Povzetek: The structural and physio-chemical properties of biochar are crucial to determining biochar’s quality and the adequate application. Specifically, the large porosity of biochar has been known as a favorable feature, especially for environmental remediation. In this regard, physical and chemical modifications have been used to improve biochar’s porosity which requires high-energy consumption and involves chemical agents. The objective of this study was to prepare biochar with developed porosity using mild treatments. Arundo donax and olive stone were demineralized by a water-washing method. Treated and non-treated biomasses were pyrolyzed, and part of the derived samples was subjected to wet ball milling. Samples were characterized with proximate, Fourier transform infrared, particle size, and physisorption analyses. The effect of demineralization depended on the biomass type, as ash reduction only influenced Arundo donax-derived biochar, which was attributed to the difference in initial ash content that was relatively low for olive stone. The carbonization yield decreased by 46% for the Arundo donax biomass after demineralization. Moreover, demineralization expanded the surface area and total pore volume of the Arundo donax biochar. The ball milling was effective in producing micro-sized biochar particles with a mean size ranging between 30 ± 2 µm and 42 ± 2 µm and between 13 ± 1 µm and 22 ± 2 µm for Arundo donax and olive stone without and with demineralization, respectively. Ball milling increased the surface area of non-demineralized Arundo donax by 47% and demineralized Arundo donax by 124%. Additionally, ball milling increased the surface area of non-demineralized olive stone by 65% and demineralized olive stone by 62%.
Ključne besede: biomass, carbonisation, porosity
Objavljeno v DiRROS: 13.02.2024; Ogledov: 47; Prenosov: 32
.pdf Celotno besedilo (2,97 MB)
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7.
Surveillance of the banks of reservoirs on the Drava River in Slovenia after extensive floods
Pavel Žvanut, 2022, objavljeni znanstveni prispevek na konferenci

Povzetek: The Slovenian section of the Drava River is 133 km long, and over this distance it has a descent of 148 m. Eight HPPs are located on this section (six directly in the river course, whereas the other two in derivation channels of the river). Ten concrete gravity dams, with a structural height between 17 and 54 m, created eight reservoirs. In addition to their main use for electricity generation, reservoirs are also used for floods mitigation, irrigation, industrial water use and recreation. At the beginning of November 2012, extremely high flows of the Drava River, which exceeded 100-year flood, caused floods in the middle and lower reaches of the river. Extraordinary visual geotechnical inspections of the banks, in order to determine any instability of them, were carried out immediately after this event. Numerous landslides and landslips were identified, as well as damage to nearby buildings, but also damage and threat to transport infrastructure. Damaged banks of reservoirs and damaged infrastructure were instantly rehabilitated. In the future, it is necessary to perform regular and extraordinary surveillance of the banks of reservoirs, drawing attention to damage that needs immediate rehabilitation, thus preventing the occurrence of eventual disastrous consequences.
Ključne besede: concrete dams, Drava river, reservoirs, derivation channels, extreme events, extensive floods, extraordinary visual inspection, Formin HPP, levee breach, great damage
Objavljeno v DiRROS: 06.02.2024; Ogledov: 65; Prenosov: 28
.pdf Celotno besedilo (18,69 MB)
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8.
Quantifying the environmental implication of cotton-fiber-based nanocrystalline cellulose : a life-cycle assessment
Katja Malovrh Rebec, Janez Turk, Matjaž Kunaver, 2024, izvirni znanstveni članek

Povzetek: Considering the increasing demand for nanocrystalline-cellulose in the industry, due to its exceptional physical and biological properties, cheaper and more efficient production processes are sought. Addressing environmental concerns, especially within the framework of EU policies, this study employs Life Cycle Assessment (LCA) to evaluate the environmental performance of a novel nanocrystalline-cellulose production procedure, encompassing biomass depolymerization, rinsing, and bleaching. The LCA aims to identify environmental hotspots, explore mitigation measures, and enables comparisons with other LCA studies on nanocrystalline-cellulose. The results are calculated and reported for 19 environmental impact categories, using the ReCiPe 2016 impact assessment method. The production of 1 kg of dry nanocrystalline-cellulose using the novel process emits 63.7 kg CO2 equivalent, which is lower than the literature average (68 kg CO2 equivalent). The solvent (e.g. diethylene glycol) is the major contributor to the global warming potential and fossil-fuel depletion potential in the product stage of the nanocellulose, while the electricity requirements and glycerin represent environmental hotspots regarding 15 of the 19 impact categories assessed. In terms of the water-consumption potential, the environmental hotspot is production of raw materials (e.g. cotton fibers). Electricity contributes more than 50 % of the burden to the impact categories associated with ionizing radiation, the pollution of aquatic ecosystems and human toxicity related to cancer. It also holds a significant share of the burdens for terrestrial acidification (48 % of the impact), the formation of fine particulate matter (46 % of the impact), and human toxicity related to non-cancer diseases (37 % of the impact). This underscores the importance of optimizing the production process, possibly through upscaling. Additionally, incorporating on-site renewable energy sources and utilizing biomass-derived diethylene glycol can enhance the environmental performance of nanocrystalline-cellulose.
Ključne besede: LCA, cascade use, cellulose nanocrystals, pilot production, environmental performance
Objavljeno v DiRROS: 06.02.2024; Ogledov: 56; Prenosov: 30
.pdf Celotno besedilo (5,07 MB)
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9.
Effect of sucrose concentration on streptococcus mutans adhesion to dental material surfaces
Anamarija Zore, Franc Rojko, Nives Matijaković Mlinarić, Jona Veber, Aleksander Učakar, Roman Štukelj, Andreja Pondelak, Andrijana Sever Škapin, Klemen Bohinc, 2024, izvirni znanstveni članek

Povzetek: Enamel demineralization, known as dental caries, is instigated by the bacterium Streptococcus mutans, which generates acid during carbohydrate metabolism. Among carbohydrates, sucrose is the most cariogenic and capable of biofilm formation. This study aimed to explore and comprehend Streptococcus mutans’ adherence to two prevalent dental material surfaces, i.e., a cobalt–chromium(Co-Cr) alloy and a resin-based composite, under the influence of various sucrose concentrations. To understand bacterial adhesion, the surfaces were characterized using profilometry, tensiometry, and surface charge measurements. Bacterial adhesion was evaluated using scanning electron microscopy and crystal violet dye methods. Results revealed that the composite surface exhibited greater rough-ness compared with the Co-Cr alloy surface. Both surfaces displayed hydrophilic properties and a negative surface charge. Bacterial adhesion experiments indicated lower bacterial adherence to the Co-Cr alloy than to the composite surface before the addition of sucrose. However, the introduction of sucrose resulted in biofilm development on both surfaces, showcasing a similar increase in bacterial adhesion, with the highest levels being observed at a 5% sucrose concentration in the bacterial suspension. In conclusion, the findings suggest sucrose-rich foods could facilitate bacterial adaptation despite less favorable surface characteristics, thereby promoting biofilm formation.
Ključne besede: bacterial adhesion, streptococcus mutans, dental material surfaces, sucrose concentration
Objavljeno v DiRROS: 31.01.2024; Ogledov: 78; Prenosov: 37
.pdf Celotno besedilo (4,28 MB)
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10.
The influence of different fibres quantity on mechanical and microstructural properties of alkali-activated foams
Katja Traven, Mark Češnovar, Barbara Horvat, Vilma Ducman, 2022, objavljeni znanstveni prispevek na konferenci

Povzetek: Alkali activated foams (AAFs) were produced using electric arc furnace steel slag (EAF) and ladle furnace basic slag (LS), obtained from two metallurgical companies in Slovenia. They were activated with a mixture of sodium water glass (Na2SiO3) and solid NaOH and foamed with hydrogen peroxide (H2O2). Pores were stabilized with the addition of Triton as a surfactant. Four types of fibres were added to the studied mixture (polypropylene (PP), polyvinyl-alcohol (PVA), basalt (B), and glass wool (GW)) in five different quantities: 0.5, 1.0, 1.25, 1.5 and 2.0 vol % in order to additionally stabilize the structure and thus improve its mechanical properties. The results of mechanical properties showed, that compressive strength was increased in all 20 specimens, partially due to the increased density as well as to the fibre addition. Flexural strength on the other hand was the most improved in the samples where PP and PVA fibres were added. The samples with the addition of B and GW fibres on the other hand showed only small or no improvement in flexural strength in comparison to the referenced sample. Additionally, the microstructure of used fibres and selected foams was also investigated by the means of SEM analysis.
Ključne besede: fibers, alkali activated foams, properties
Objavljeno v DiRROS: 31.01.2024; Ogledov: 67; Prenosov: 31
.pdf Celotno besedilo (4,05 MB)
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