Institutt for bygg, energi og materialteknologi: Nye registreringer
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Investigating the Influence of Oil Shale Ash and Basalt Composite Fibres on the Interfacial Transition Zone in Concrete
(Conference object; Konferansebidrag, 2024-02) -
Damage Accumulation in the Hybrid Composite Material Reinforced by Oil Shale Ash (OSA) Powder and 3D-Knitted Fabric Subjected to Mechanical Loading
(Journal article; Tidsskriftartikkel, 2024-02-23)Hybrid reinforcement in a composite material (CM), in many situations, allows better govern material mechanical properties. Polymer matrix CM plate is reinforced with small particles and macro-fibers. Particles are oil shale ash (OSA) powder, macro-fibers – basalt fiber threads im-pregnated by matrix material. With the goal to find out elastic properties of the matrix- polymer with OSA, samples with ... -
INFLUENCE OF PARTICULATE MIXTURE CONTAINING STABILISED WOOD ON LONG-TERM BEHAVIOUR OF WOOD-CEMENT COMPOSITES. CASE STUDY
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024)This paper presents research on the changes in the properties of cement-bonded particleboard modified with particulate mixture (PM). PM replaced 4% of the binder (cement) and 4% of the filler (spruce chips). The cement-bonded particleboards were tested for physical (bulk density, swelling, linear expansion due to relative humidity changes) and mechanical properties (modulus of rupture and modulus ... -
The Effect of Raw Materials and Mechanical Activation Stages on Properties of Foamed Concrete
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-02-16)This study investigates the impact of high-energy milling on foamed concrete, which is crucial for its lightweight and insulating properties. The research uses a two-rotor disintegrator for milling cement, sand, and microsilica to evaluate the mechanical properties of foamed concrete produced with a high-speed homogenizer in a novel two-stage process. Comparisons are made between non-milled, ... -
Modification of glass screen printed electrodes with graphene quantum dots for enhanced power output in miniaturized microbial fuel cells
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-12-02)This paper demonstrates screen-printing technique, Glass Screen printed (GSP) on glass layer with Graphene Quantum Dots (GQDs) via drop casting approach to manufacture electrodes for Miniaturized Microbial Fuel Cells (MMFCs). MMFCs are viable options to sustainably operate low-power devices such as sensors, implantable medical devices, etc. However, the technology is still not fully mature for ... -
Healthcare waste management and antimicrobial resistance: a critical review
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-10-30)The rapid growth of populations and urbanization has led to a significant increase in healthcare waste, posing serious health risks. A search on Google Scholar identified seven relevant articles from Ethiopia that examine the relationship between improper waste management in healthcare facilities (HCFs) and the rise of antimicrobial resistance (AMR) genes. This review aims to highlight key concepts, ... -
Durability of Wood–Cement Composites with Modified Composition by Limestone and Stabilised Spruce Chips
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-12-23)Limestone (LS) and stabilised secondary spruce chips (SCs) utilisation in wood–cement composites is still an unexplored area. Therefore, the main objective of the research presented here is the assessment of the long-term behaviour of cement-bonded particleboards (CBPs) modified by LS and SCs. Cement (CE) was replaced by 10% of LS, and spruce chips by 7% of SCs. The test specimens were stored ... -
Modelling ductile fracture in an Al alloy with crystal plasticity models
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-04-24)Crystal plasticity models enhanced with coupled or uncoupled damage and fracture criteria give an opportunity to account for the role of microstructure in ductile fracture, most directly representing the local variations of stress and strain fields inside and between the grains, voids and particles. Some computationally efficient crystal plasticity, damage and fracture models have recently been ... -
Frost durability of cementitious materials: What's next?
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-23)Frost durability, a critical parameter for concrete, especially in harsh exposure regions, has been extensively researched, with almost four thousand papers published since the 1970s. However, a systematic mapping of this research is yet to be explored. This paper presents a novel approach based on Natural Language Processing (NLP) and machine learning to semi-automatically analyze the ... -
The effect of oil shale ash and basalt-boron fiber on waste package gamma-radiation shielding properties
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-24)Oil shale ash is an abundant industrial residue that contains hydration products, which have been shown to immobilize heavy metals. The use of innovative additives such as oil shale ash (OSA) and basal-fiber materials containing boron (BBF) have not been thoroughly investigated. This study analyzes the potential of OSA-BBF concrete as an overpack material for low- and intermediate-level radioactive ... -
An experimental study of effect of printed thickness on the mechanical properties of LPBF produced AlSi10Mg
(Chapter; Bokkapittel, 2024-04-24)Additive manufacturing process allows fabrication of parts with a broad range of sizes with high resolution. This size variation introduces new mechanical properties within the printed component, which creates a significant challenge for the qualification of additively manufactured parts. This unresolved issue hinders the implementation of additive manufacturing in high performance engineering ... -
Investigation into Using CFD for Estimation of Ship Specific Parameters for the SPICE Model for Prediction of Sea Spray Icing: Part 1—The Proposal
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-10-18)A machine learning model for prediction of icing on vessels and offshore structures, Spice, was recently developed by Deshpande 2023. Some variables required for the prediction of icing rates in most prediction models, including Spice, such as the spray flux, cannot be easily measured. Existing models estimate these using empirical formulations that have been heavily criticized. Most existing models ... -
An Investigation into Using CFD for the Estimation of Ship Specific Parameters for the SPICE Model for the Prediction of Sea Spray Icing: Part 2—The Verification of SPICE2 with a Full-Scale Test
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-10-18)A hybrid CFD–ML model for the prediction of sea spray icing, SPICE2, was developed in Part 1 of this study in Deshpande et al., 2024. The SPICE2 model is an extension of the ML model, SPICE, where some of the variables required for icing rate predictions: local wind speed, spray duration, spray period, and spray flux, are computed from CFD simulations. These, along with the air and water ... -
An alternative two-phase formulation and analytical solution for a Stefan problem in one-dimension accounting for volume change and sensible heat
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-09)Stefan problems, or free boundary problems, in the phase change process occur in many engineering problems. This paper develops a compact formula for a two-phase melting process in a one-dimensional semi-infinite slab with a novel approach. Unlike the classic Stefan problem, the novel approach considers volume change (or density difference) and the net-sensible-heat of the two phases. Furthermore, ... -
Full-scale tests of deicing with seawater
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-16)Sea-spray icing is one of the major hazards for small- and medium-sized vessels in polar regions. Predominant anti- and deicing measures include prevention by heeding the weather forecasts and avoiding high-risk situations, protection by enclosing exposed and high-priority areas, manual ice removal by personnel, heat tracing and surplus heat. Energy is in limited supply on vessels, and alternative ... -
Investigating the Influence of Oil Shale Ash and Basalt Composite Fibres on the Interfacial Transition Zone in Concrete
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-06-27)The interfacial transition zone (ITZ) is the weakest phase in concrete, characterised by higher porosity and being prone to microcrack formation. Additionally, the ITZ is created when dispersed fibre reinforcement is present. Although fibres improve flexural strength, they can negatively impact other properties. This research investigates the ITZ of fibre-reinforced concrete where macro-basalt fibres ... -
Repair Options for Corrosion-damaged Prestressed Concrete Structures
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-05)Prestressing of bridges allows construction of long spanned bridges made from thin structural members with high flexural and shear capacity. Studies have shown that some of the existing prestressed bridges are not meeting their designed service life due to corrosion of the tendons. The main reasons are poor construction practices in combination with inadequate inspection and maintenance plans. ... -
An experimental study on thermophysical properties of nano- TiO2-enhanced phase change materials for cold climate applications
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-01-30)In high-energy-demand regions, such as the Arctic, the building sector is focused on reducing the carbon footprint and mitigating environmental impact. To achieve this, phase change materials (PCMs) are being investigated for thermal energy storage due to their high latent heat of fusion. However, their limited applications arise from poor thermal conductivity. In addressing this issue, the ... -
Mechanical Properties of MiniBars™ Basalt Fiber-Reinforced Geopolymer Composites
(Journal article; Tidsskriftartikkel, 2024-01-02)Fly ash-based geopolymers represent a new material, which can be considered an alternative to ordinary Portland cement. MiniBars™ are basalt fiber composites, and they were used to reinforce the geopolymer matrix for the creation of unidirectional MiniBars™ reinforced geopolymer composites (MiniBars™ FRBCs). New materials were obtained by incorporating variable amount of MiniBars™ (0, 12.5, 25, 50, ... -
Experimental Insights into the Fermentation of Pyro-Syngas to Ethanol in a Semi-Batch and Continuous Stirred Bioreactor with Mathematical Modelling and Optimization
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-01-24)Syngas fermentation can play an important role in implementing the concept of biorefinery as it can serve as a platform to convert high-lignin biomass to biofuels. For the utilization of this process in commercial scale, the generation of an experimental database supported by a deterministic mathematical model and optimization is necessary. In this study, a locally isolated clostridial consortium, ...