Academic literature on the topic 'Basalt fibre'
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Journal articles on the topic "Basalt fibre"
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Hasham, Md, V. Reddy Srinivasa, M. V. Seshagiri Rao, and S. Shrihari. "Flexural behaviour of basalt fibred concrete slabs made with basalt fibre reinforced polymer rebars." E3S Web of Conferences 309 (2021): 01055. http://dx.doi.org/10.1051/e3sconf/202130901055.
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In this paper, the flexural behaviour of M30 grade basalt fibred concrete slabs made with basalt fibre reinforced polymer rebars are studied and compared with slabs made with steel rebars. The optimum percentage of basalt is 0.3% for 50mm length basalt fibres. Due to high particle packing density in concrete made with basalt fibre micro cracks are prevented due to enhanced fatigue and stress dissipation capacity. Addition of basalt fibres to enhances the energy absorbtion capacity or toughness thereby enhancing the resistance to local damage and spalling. Addition of basalt fibres controlled the crack growth and crack width. Load at first crack of M30 grade basalt fibred concrete slabs made with basalt fibre reinforced polymer rebars is more than M30 grade conventional concrete slabs made with steel rebars because the with addition of basalt and BFRP bars will make either the interfacial transition zone (ITZ) strong or due to bond strength of concrete slabs made with basalt fibre reinforced polymer rebars. The ultimate strength in M30 grade basalt fibred concrete slabs made with basalt fibre reinforced polymer rebars is more than conventional concrete slabs made with steel rebars. Deflection at the centre of M30 grade basalt fibred concrete slabs made with basalt fibre reinforced polymer rebars is almost double than the conventional concrete slabs made with steel rebars. Toughness indices evaluated for M30 grade basalt fibred concrete slabs made with basalt fibre reinforced polymer rebars indicates that basalt fibre and BFRP bars will enhance the energy absorbtion capacity of slabs.
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Simon, Seena, Arun Prathap, Sharanya Balki, and R. G. Dhilip Kumar. "An Experimental Investigation on Concrete with Basalt Rock Fibers." Journal of Physics: Conference Series 2070, no. 1 (November 1, 2021): 012196. http://dx.doi.org/10.1088/1742-6596/2070/1/012196.
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Abstract Basalt fibre is formed from basalt rock when melted at a high temperature making it a non-metallic fibre. Basalt fibre reinforced concrete are good fire resistance, strength and light weight. These properties making it highly advantageous in the future to the construction business. There are many applications of basalt fibre like industrial, bridges, residential and highway etc. Fibres of basalt rock are used to make Basalt fibre, is cheaper and have improved physicomechanical properties which is very similar to the fibre glass and the carbon. They can replace many expensive materials resulting in wide range of applications in the field. The raw materials are available in all countries, making their production very simple. The biggest difficulties of the concrete and cement industry’s can be solved by the usage of basalt fibres. It is also used as composite and in the aerospace, automotive industries and fibre proof textile. Basalt fibres have no hazardous reactions with water or air and are explosion-proof and non-combustible. No chemical reaction will be produced that may damage environment or health when in contact with other chemicals. Reinforced plastics and steel maybe replaced by the basalt base composites. One kg of basalt reinforces equals to 9.6 kg of steel. Differences in compressive strength and split tensile test for concrete with and without basalt fibre by using cubes and cylinders are studied in this paper.
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Goud, E. Giri Prasad, Dinesh Singh, V. Srinivasa Reddy, and Kaveli Jagannath Reddy. "Stress-Strain behaviour of basalt fibre reinforced concrete." E3S Web of Conferences 184 (2020): 01081. http://dx.doi.org/10.1051/e3sconf/202018401081.
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This paper prophesies the stress strain behaviour of M30 grade concrete reinforced with basalt fibres of length 12 mm, 36 mm and 50 mm of amounts 0.4%, 0.4% and 0.3% by volume of concrete respectively. Modulus of elasticity and toughness of M30 grade basalt fibre reinforced concretes are also evaluated. It was found that BFRCC mixes show good resistance to impact and has superior dissipation capacity. The optimal basalt fibre volume fraction is 0.3% and length is 50 mm. For this case, toughness index and energy absorbed at fracture have considerably enhanced. With the volume fraction of basalt fiber exceeding the optimum volume fraction, the mechanical properties of basalt fiber are weakened.
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Nandagopal, K. R., A. Selvakumar, and D. Raja. "Effect of Atmospheric Pressure Oxygen Plasma treatment on Bonding Characteristics of Basalt Fibre Reinforced Concrete." Fibres and Textiles in Eastern Europe 29, no. 4(148) (August 31, 2021): 90–93. http://dx.doi.org/10.5604/01.3001.0014.6348.
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In this research work, the bonding characteristics of plasma treated basalt fibres were analysed by employing the fibre pull-out test. 80 samples were prepared with two different spans of basalt fibres (such as 25 mm and 50 mm) and four levels of embedded length (10, 15, 20 and 25) inside standard M20 grade concrete. Debonding and bonding characteristics of the plasma treated fibres were compared with raw basalt fibres through the fibre pull-out test. The plasma treated and raw basalt fibres were characterised through Field emission scanning electron microscope (FESEM) and Fourier transform infrared (FTIR) analysis. It was observed that confirmation of the presence of hydroxyl groups on the basalt fibre surface was realised through the FTIR test and that there was higher adsorption of concrete particles by the plasma treated basalt fibres through FESEM. The de bonding and fibre pull-out energy of the plasma treated basalt fibres were improved by about 9% and 10% compared with 25 mm and 50 mm raw basalt fibres. From the observation above, it can be stated that the surface modification of basalt fibre may lead to a change in the debonding and pull-out energy level.
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Xu, Shengtang, Chaofan Wu, Jinchao Yue, and Zikai Xu. "Shrinkage and Mechanical Properties of Fibre-Reinforced Blast Furnace Slag-Steel Slag-Based Geopolymer." Advances in Civil Engineering 2022 (April 8, 2022): 1–10. http://dx.doi.org/10.1155/2022/8931401.
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Geopolymer materials have several obvious advantages such as energy conservation, emission reduction, and waste reuse, so they can become substitutes for cement materials. In this study, geopolymer mortars made from blast furnace slag and steel slag reinforced by basalt fibre and polyvinyl alcohol (PVA) fibre were prepared to explore the effect on their strength and shrinkage properties. Scanning electron microscopy (SEM) was employed to characterize the reaction mechanism of the geopolymer mortars. The results show that both PVA fibre and basalt fibre can improve the mechanical properties of geopolymer mortars during the late curing period. The geopolymer reinforced by basalt fibre manifested a better toughness. A proper content of PVA fibres and basalt fibres can effectively reduce the drying and autogenous shrinkage of geopolymer mortars. The optimal content of basalt fibres and PVA fibres to reduce the drying shrinkage was 0.4%. The SEM results show that the fibres can effectively alleviate the stress concentration and prevent crack propagation.
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Xiao, Jie, Han Shi, Lei Tao, Liangliang Qi, Wei Min, Hui Zhang, Muhuo Yu, and Zeyu Sun. "Effect of Fibres on the Failure Mechanism of Composite Tubes under Low-Velocity Impact." Materials 13, no. 18 (September 17, 2020): 4143. http://dx.doi.org/10.3390/ma13184143.
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Filament-wound composite tubular structures are frequently used in transmission systems, pressure vessels, and sports equipment. In this study, the failure mechanism of composite tubes reinforced with different fibres under low-velocity impact (LVI) and the radial residual compression performance of the impacted composite tubes were investigated. Four fibres, including carbon fiber-T800, carbon fiber-T700, basalt fibre, and glass fibre, were used to fabricate the composite tubes by the winding process. The internal matrix/fibre interface of the composite tubes before the LVI and their failure mechanism after the LVI were investigated by scanning electric microscopy and X-ray micro-computed tomography, respectively. The results showed that the composite tubes mainly fractured through the delamination and fibre breakage damage under the impact of 15 J energy. Delamination and localized fibre breakage occur in the glass fibre-reinforced composite (GFRP) and basalt fibre-reinforced composite (BFRP) tubes when subjected to LVI. While fibre breakage damage occurs globally in the carbon fibre-reinforced composite (CFRP) tubes. The GFRP tube showed the best impact resistance among all the tubes investigated. The basalt fibre-reinforced composite (BFRP) tube exhibited the lowest structural impact resistance. The impact resistance of the CFRP-T700 and CFRP-T800 tube differed slightly. The radial residual compression strength (R-RCS) of the BFRP tube is not sensitive to the impact, while that of the GFRP tube is shown to be highly sensitive to the impact.
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El-Gelani, A. M., C. M. High, S. H. Rizkalla, and E. A. Abdalla. "Effects of Basalt Fibres on Mechanical Properties of Concrete." MATEC Web of Conferences 149 (2018): 01028. http://dx.doi.org/10.1051/matecconf/201814901028.
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This paper presents the results of an experimental program carried out to investigate the effects of Basalt Fibre Reinforced Polymers (BFRP) on some fundamental mechanical properties of concrete. Basalt fibres are formed by heating crushed basalt rocks and funnelling the molten basalt through a spinneret to form basalt filaments. This type of fibres have not been widely used till recently. Two commercially available chopped basalt fibres products with different aspect ratios were investigated, which are dry basalt (GeoTech Fibre) and basalt pre-soaked in an epoxy resin (GeoTech Matrix) .The experimental work included compression tests on 96 cylinders made of multiple batches of concrete with varying amounts of basalt fibre additives of the two mentioned types, along with control batches containing no fibres. Furthermore, flexural tests on 24 prisms were carries out to measure the modulus of rupture, in addition to 30 prisms for average residual strength test. Results of the research indicated that use of basalt fibres has insignificant effects on compressive strength of plain concrete, where the increase in strength did not exceed about 5%. On the other hand, results suggest that the use of basalt fibres may increase the compressive strength of concrete containing fly as up top 40%. The rupture strength was increased also by 8% to 28% depending on mix and fibre types and contents. Finally, there was no clear correlation between the average residual strength and ratios of basalt fibres mixed with the different concrete batches.
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Bhat, T., D. Fortomaris, E. Kandare, and A. P. Mouritz. "Properties of thermally recycled basalt fibres and basalt fibre composites." Journal of Materials Science 53, no. 3 (October 17, 2017): 1933–44. http://dx.doi.org/10.1007/s10853-017-1672-7.
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Liu, Hua Wu, Kai Fang Xie, Wei Wei Hu, Han Sun, Shu Wei Yang, and Tian Yang Yang. "Strengths of Basalt Fiber Reinforced Fir Sawdust Panel." Advanced Materials Research 821-822 (September 2013): 1159–63. http://dx.doi.org/10.4028/www.scientific.net/amr.821-822.1159.
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Wood composite is weak under heavy loadings, which was improved by reinforcing basalt fibres. In this study, chopped basalt fibres with different lengths (5mm, 10mm, 15mm and 20mm) were mixed with fir sawdust at 2.5%, 5%, 7.5% and 10% weight fractions to produce basalt fiber reinforced fir sawdust panels. The reinforced panels showed improved strength values. A maximum bending strength value of 44.1 MPa was obtained when the mean length of chopped basalt fiber was 15mm and the weight fraction was 2.5%. The tensile strength reached a maximum value of 17.4MPa when the mean length of basalt fiber was 10mm and the weight fraction was 10%. Compared with the unreinforced fir sawdust panel group, the reinforced panel group increased bending strength 60.7% and had a 47.5% increase in tensile strength. These findings demonstrate that basalt fibre has very promising prospects for strength improving.
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Chowdhury, Indraneel R., Richard Pemberton, and John Summerscales. "Developments and Industrial Applications of Basalt Fibre Reinforced Composite Materials." Journal of Composites Science 6, no. 12 (December 5, 2022): 367. http://dx.doi.org/10.3390/jcs6120367.
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Basalt mineral fibre, made directly from basalt rock, has good mechanical behavior, superior thermal stability, better chemical durability, good moisture resistance and can easily be recycled when compared to E-glass fibres (borosilicate glass is called ‘E-glass’ or ‘electric al-grade glass’ because of its high electrical resistance) which are traditionally used in structural composites for industrial applications. Industrial adoption of basalt fibre reinforced composites (FRC) is still very low mainly due to inadequate data and lower production volumes leading to higher cost. These reasons constrain the composites industry from seriously considering basalt as a potential alternative to conventional (e.g., E-glass) fibre reinforced composites for different applications. This paper provides a critical review of the state-of-the-art concerning basalt FRC highlighting the increasing trend in research and publications related to basalt composites. The paper also provides information regarding physico-chemical, and mechanical properties of basalt fibres, some initial Life cycle assessment inventory data is also included, and reviews common industrial applications of basalt fibre composites.
Dissertations / Theses on the topic "Basalt fibre"
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Borhan, Tumadhir Merawi. "Thermal and structural behaviour of basalt fibre reinforced glass concrete." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/thermal-and-structural-behaviour-of-basalt-fibre-reinforced-glass-concrete(2fcc3a9a-2012-4261-966b-4ff37420e032).html.
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This study aims to produce a type of concrete with both good thermal and mechanical properties by using environmentally friendly and low cost materials. In addition, the resistance of this concrete to fire conditions was investigated. The experimental work comprises two parts. In the first part, recycled glass was used as a partial replacement for natural sand (at proportions 20%, 40% and 60%) together with basalt fibre having different volume fractions (0.1%, 0.3%, and 0.5%). The results obtained from the experimental work showed that the optimum content is 20% glass and at 28 days, there was a 4.23% and 15% enhancement in the compressive strength and the splitting tensile strength respectively. Above 20% glass there was a slight reduction (6.6% and 22%) in the compressive strength and the splitting tensile strength when 60% glass was used. The results also showed that when glass sand and basalt fibre content increase, there is a decrease in the thermal conductivity range from 4.35% to 50% at temperature levels between 60oC to 600oC. The structural behaviour of this type of concrete was investigated in the second part of this study by carrying out small-scale slab tests at ambient and elevated temperatures. The results show that there is an increase in the load carrying capacity above the theoretical yield line load, due to membrane action, for all percentages of glass and volume fractions of basalt fibre ranging from 1.35 to 1.68 for the slab tested at ambient temperature and from 3.13 to 3.26 for the slabs tested at elevated temperature. Also the slabs with higher glass sand and basalt fibre content had a higher load enhancement and failed at a higher displacement compared to the control mix.A comparison between the simplified method and the finite element software package ABAQUS showed that the ABAQUS model gives reasonable predictions for the load-vertical displacement and the temperature-displacement relationships at both ambient and elevated temperature conditions, while the simplified method gives conservative predictions for the maximum allowable vertical displacement for the slab at elevated temperature. A parametric study showed that a 10 mm cover depth is the optimum depth as well as the reinforcement temperature predicted reduced with increasing load ratio (applied load/yield line load).
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Seghini, Maria Carolina. "Mechanical Analysis and Fibre/Matrix Interface Optimization for Next Generation of Basalt-Plant Fibre Hybrid Composites." Electronic Thesis or Diss., Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2020. http://www.theses.fr/2020ESMA0003.
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La prise de conscience mondiale des enjeux environnementaux a conduit à l’émergence de composites«verts», dans lesquels les fibres naturelles sont amenées à remplacer les fibres synthétiques. Ces nouveaux matériaux offrent des alternatives écologiques aux composites synthétiques traditionnels mais sont difficilement utilisables pour des applications semi-structurales ou structurales. Une solution possible à ce problème est le développement des composites hybrides, en combinant ensemble fibres naturelles et synthétiques. Dans ce cadre, l'objectif de cette étude était de développer des composites hybrides à base de fibres de basalte et de lin. Les composites hybrides ont été élaborés par moulage par infusion sous vide avec une matrice époxy. À des fins de comparaison,des composites 100% à fibres de lin et100%à fibres de basalte ont également été produits. Une caractérisation mécanique quasi-statique et dynamique amontré que l'hybridation permet d’obtenir un composite avec des propriétés mécaniques intermédiaires comparées à celles des composites à fibres de lin ou de basalte. Cependant, l’analyse approfondie des dommages a montré la nécessité d'optimiser la qualité d'adhésion de l'interface fibre/matrice afin d'accroître les performances mécaniques des composites hybrides obtenus. Pour cette raison, différents traitements de modification de surface ont été développés et étudiés pour les fibres de lin et de basalte. Un traitement physique par plasma (Plasma Enhanced Chemical Vapor Deposition) a été appliqué aux fibres de lin et de basalte. Les fibres de lin ont également été soumises à deux traitements chimiques utilisant des espèces enzymatiques et du CO2supercritique. Les effets des traitements sur la stabilité thermique, la morphologie et les propriétés mécaniques des fibres de lin et de basalte ont été étudiés. L’adhérence fibre/matrice a été analysée en réalisant des tests de fragmentation sur des composites monofilamentaires. La qualité de l'adhésion entre les fibres et les matrices époxy et vinylester a été évaluée en termes de longueur critique de fragment, de longueur de décohésion interfaciale et de résistance au cisaillement interfacial. La micto-tomographie haute résolution a été utilisée pour analyser les mécanismes d'endommagement lors des tests de fragmentation. Pour les deux types de fibres, les meilleurs résultat sont été obtenus grâce au traitement par plasma. Ce traitement a consisté à déposer un revêtement homogène de tétravinylsilane à la surface des fibres de basalte et de lin, ce qui a permis une augmentation significative de l’adhérence fibre/matrice, ouvrant ainsi la voie à la prochaine génération de composites hybrides plus respectueux de l’environnement et utilisables pour des applications semi-structuralesGlobal awareness of environmental issues has resulted in the emergence of “green” composites, in which natural fibres are used to replace synthetic ones. However, in semi-or structural applications, it can be inconvenient to use composites based on natural fibres. A possible solution to this problem is the development of hybrid composite materials, combining together plies of natural and synthetic fibres. In this framework, the aim of this research project was to develop basalt-flax fibre hybrid composites with a view to obtaining more environmentally friendly composites for semi-structural applications. Hybrid composites were produced through vacuum infusion molding with epoxy matrix.For comparison purposes, 100% flax fibre composites and 100% basalt fibre composites were also manufactured. A quasi-static and dynamic mechanical characterization showed that the hybridization allows the production of a composite with intermediate mechanical performances compared to those possessed by flax and basalt composites. However, the damage analysis has revealed the need to optimize the fibre/matrix interface adhesion quality, in order to increase the mechanical properties of the resulting hybrid composites. For this reason, different surface modification treatments have been specifically designed and investigated for flax and basalt fibres. Flax and basalt fibres were treated by the physical process of Plasma Enhanced Chemical Vapor Deposition. Flax fibres were also subjected to two chemical treatments using enzymatic species and supercritical CO2. The effects of the surface modification treatments on the thermal stability, morphology and mechanical properties of flax and basalt fibres have been investigated. The degree and extent of fibre/matrix adhesion were analyzed by micromechanical fragmentation tests on monofilament composites. The adhesion quality between fibres and both epoxy and vinylester matrices has been assessed in terms of critical fragment length, debonding length and interfacial shear strength. High-resolution μ-CT has been used to support the analysis of the damage mechanisms during fragmentation tests. For both flax and basalt fibres, the best results were obtained after the plasma polymer deposition process. This process was able to produce a homogeneous tetravinylsilane coating on the surface of basalt and flax fibres, which resulted in a significant increase in the fibre/matrix adhesion, thus paving the way for the next generation of more environmentally friendly hybrid composites for semi-structural applications
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Rengarajan, Muralidharan. "Laboratory testing of shotcrete with fibres of steel, basalt or synthetic materials." Thesis, KTH, Betongbyggnad, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-287310.
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Shotcrete or sprayed concrete has become an inevitable material for stabilising and supporting hard rock tunnels. To prevent rock block fallouts in the excavated tunnel, shotcrete is pneumatically projected under high pressure on the rock surface. This method has proven to reduce the construction time drastically, and the addition of fibres in the shotcrete material results in Fibre Reinforced Shotcrete (FRS). The fibres increased the strength of the parent matrix and made the reinforcement bar (mesh) placing procedure with its heavy labour work unnecessary. Even though FRS have been in use for many years, to design FRS lining there are currently no complete, widely used guidelines. Traditionally, the most frequently used testing was a traditional beam testing method which helps to determine the FRS mechanical properties. Previous studies prove that the result from beams often show a high scatter in the results. Another proposed standard testing method is the Round Determinate Panel method to determine the energy absorption capacity. This method has the potential to be a reliable test procedure with a repeatable and predictable crack pattern.In this project, an experimental investigation was carried out to understand the behaviour of macro fibres of steel, basalt and synthetic materials in FRS. The specimens were sprayed in situ and cast in laboratory, of which the in situ samples were assigned to different curing conditions. The test standard ASTM C-1550 was used to design the round panels and SS-EN 14488-3 for the beams. Each type of FRS specimen’s compressive strength was tested, evaluated and compared. The single fibre pullout strength was tested to determine the bond strength between shotcrete and fibres.The calculated results showed the coefficient of variation (COV) of energy absorption capacity from panels varied within 3 % – 13 % and the residual strength of beams within 12 % – 35 %. Irrespective of testing method, the Dramix 3D steel fibre and Minibars basalt fibre for the tested cases showed the lowest dispersion of result. Minibars showed a significant increase in compressive strength compared to the other fibres. Single fibre pullout testing concluded that the steel fibre had superior load capacity at the first crack. Minibars showed a strength close to that of steel fibres and a failure mode similar to that with synthetic fibres.
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Ammar, Mohamed Amine. "Bond durability of basalt fibre-reinforced polymers (BFRP) bars under freeze-and-thaw conditions." Thesis, Université Laval, 2014. http://www.theses.ulaval.ca/2014/30559/30559.pdf.
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Ce mémoire présente les résultats de l’étude de l’adhérence entre les barres en polymères renforcés de fibres de Basalte (PRFB) et le béton. Cinquante-quatre cylindres renforcés par des barres en PRFB et dix-huit cylindres renforcés par des barres en polymères renforcés de fibres de fibres de Verre (PRFV) ont été testés par le test d’arrachement. Les paramètres des tests incluent le type de la barre utilisée, le diamètre de la barre, la longueur d’ancrage et le nombre de cycles de gel-dégel (100 et 200 cycles). Les courbes adhérence-glissement des barres en PRFB et PRFV révèlent la même tendance. Les influences des différents paramètres sur l’adhérence ont été analysées. Les modèles analytiques BPE, BPE-modifié et CMR ont été calibrés pour décrire la relation adhérence-glissement des barres en PRFB. Les résultats montrent la capacité des barres en PRFB à remplacer les barres en PRFV dans le renforcement des structures.This thesis presents the test results of a study on the bond behavior of basalt fiber-reinforced polymers (BFRP) bars in concrete. Forty-five cylinders reinforced with BFRP bars and eighteen cylinders reinforced with glass fiber-reinforced polymer (GFRP) bars were tested in direct pullout conditions. Test parameters included the FRP material, the bar diameter, the bar’s embedment length in concrete and the number of freeze-and-thaw cycles (100 and 200 cycles). Bond-slip curves of BFRP and GFRP bars revealed similar trend. All BFRP specimens failed in a pullout mode at the bar-epoxy interface. The influence of various parameters on the overall bond performance of BFRP bars is analyzed. The BPE, modified-BPE, and CMR analytical models were calibrated to describe the bond-slip relationships of BFRP bars. Results demonstrate the promise of using BFRP bars as an alternative to GFRP bars in reinforcing concrete elements.
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Mahroug, Mohamed E. M. "Behaviour of continuous concrete slabs reinforced with FRP bars. Experimental and computational investigations on the use of basalt and carbon fibre reinforced polymer bars in continuous concrete slabs." Thesis, University of Bradford, 2013. http://hdl.handle.net/10454/6332.
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An investigation on the application of basalt fibre reinforced polymer (BFRP) and carbon fibre reinforced polymer (CFRP) bars as longitudinal reinforcement for simple and continuous concrete slabs is presented. Eight continuously and four simply concrete slabs were constructed and tested to failure. Two continuously supported steel reinforced concrete slabs were also tested for comparison purposes. The slabs were classified into two groups according to the type of FRP bars. All slabs tested were 500 mm in width and 150 mm in depth. The simply supported slabs had a span of 2000 mm, whereas the continuous slabs had two equal spans, each of 2000 mm. Different combinations of under and over FRP (BFRP/CFRP) reinforcement at the top and bottom layers of slabs were investigated. The continuously supported BFRP and CFRP reinforced concrete slabs exhibited larger deflections and wider cracks than the counterpart reinforced with steel. The experimental results showed that increasing the bottom mid-span FRP reinforcement of continuous slabs is more effective than the top over middle support FRP reinforcement in improving the load capacity and reducing mid-span deflections.
Design guidelines have been validated against experimental results of FRP reinforced concrete slabs tested. ISIS¿M03¿07 and CSA S806-06 equations reasonably predicted the deflections of the slabs tested. However, ACI 440¿1R-06 underestimated the deflections, overestimated the moment capacities at mid-span and over support sections, and reasonably predicted the load capacity of the continuous slabs tested.
On the analytical side, a numerical technique consisting of sectional and longitudinal analyses has been developed to predict the moment¿curvature relationship, moment capacity and load-deflection of FRP reinforced concrete members. The numerical technique has been validated against the experimental test results obtained from the current research and those reported in the literature. A parametric study using the numerical technique developed has also been conducted to examine the influence of FRP reinforcement ratio, concrete compressive strength and type of reinforcement on the performance of continuous FRP reinforced concrete slabs. Increasing the concrete compressive strength decreased the curvature of the reinforced section with FRP bars. Moreover, in the simple and continuous FRP reinforced concrete slabs, increasing the FRP reinforcement at the bottom layer fairly reduced and controlled deflections.
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Mahroug, Mohamed Elarbi Moh. "Behaviour of continuous concrete slabs reinforced with FRP bars : experimental and computational investigations on the use of basalt and carbon fibre reinforced polymer bars in continuous concrete slabs." Thesis, University of Bradford, 2013. http://hdl.handle.net/10454/6332.
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An investigation on the application of basalt fibre reinforced polymer (BFRP) and carbon fibre reinforced polymer (CFRP) bars as longitudinal reinforcement for simple and continuous concrete slabs is presented. Eight continuously and four simply concrete slabs were constructed and tested to failure. Two continuously supported steel reinforced concrete slabs were also tested for comparison purposes. The slabs were classified into two groups according to the type of FRP bars. All slabs tested were 500 mm in width and 150 mm in depth. The simply supported slabs had a span of 2000 mm, whereas the continuous slabs had two equal spans, each of 2000 mm. Different combinations of under and over FRP (BFRP/CFRP) reinforcement at the top and bottom layers of slabs were investigated. The continuously supported BFRP and CFRP reinforced concrete slabs exhibited larger deflections and wider cracks than the counterpart reinforced with steel. The experimental results showed that increasing the bottom mid-span FRP reinforcement of continuous slabs is more effective than the top over middle support FRP reinforcement in improving the load capacity and reducing mid-span deflections. Design guidelines have been validated against experimental results of FRP reinforced concrete slabs tested. ISIS-M03-07 and CSA S806-06 equations reasonably predicted the deflections of the slabs tested. However, ACI 440-1R-06 underestimated the deflections, overestimated the moment capacities at mid-span and over support sections, and reasonably predicted the load capacity of the continuous slabs tested. On the analytical side, a numerical technique consisting of sectional and longitudinal analyses has been developed to predict the moment-curvature relationship, moment capacity and load-deflection of FRP reinforced concrete members. The numerical technique has been validated against the experimental test results obtained from the current research and those reported in the literature. A parametric study using the numerical technique developed has also been conducted to examine the influence of FRP reinforcement ratio, concrete compressive strength and type of reinforcement on the performance of continuous FRP reinforced concrete slabs. Increasing the concrete compressive strength decreased the curvature of the reinforced section with FRP bars. Moreover, in the simple and continuous FRP reinforced concrete slabs, increasing the FRP reinforcement at the bottom layer fairly reduced and controlled deflections.
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Scheffler, Christina, Theresa Förster, and Edith Mäder. "Beschleunigte Alterung von Glasfasern in alkalischen Lösungen: Einflüsse auf die mechanischen Eigenschaften." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1244042771688-80994.
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In alkalischen Lösungen führt die Reaktion von Hydroxylionen mit den Si-O-Si-Bindungen des Glasnetzwerks zur Bildung hydratisierter Oberflächen und gelöstem Silikat. Der Grad der Korrosion bzw. der Alterung der Glasfaser ist abhängig von der chemischen Zusammensetzung des Glases und Korrosionslösung sowie von Zeit und Temperatur. Die Untersuchung von Glasfasern verschiedener chemischer Zusammensetzung in NaOH- sowie Zementlösungen zeigte, dass die inhibierende Wirkung von Ca-Ionen zu einem veränderten Korrosionsmechanismus führt. Dies konnte anhand der mechanischen Eigenschaften der Glasfasern sowie rasterelektronenmikroskopischen Untersuchungen gezeigt werden. Während die Korrosion in NaOH-Lösung zu einer ausgeprägten Umwandlung der gesamten äußeren Glasfaserschicht in Reaktionsprodukte führte, zeigten Glasfasern in Zementlösung bei gleichem pH-Wert einen stark lokal begrenzten, punktförmigen Angriff. Daraus resultieren unterschiedliche mechanische Eigenschaften der Glasfasern in Abhängigkeit von der gewählten Korrosionslösung.
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Hamed, Sarah. "Shear Contribution of Basalt Fiber-Reinforced Concrete Reinforced with Basalt Fiber-Reinforced Polymer Bars." Master's thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/34008.
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Cette étude évalue expérimentalement et analytiquement le comportement au cisaillement des poutres en béton renforcé de fibres de basalte (BRFB) renforcées longitudinalement avec des barres en polymère renforcé de fibres de basalte (PRFB). Un nouveau type de macro-fibres de basalte a été ajouté au mélange de béton pour produire le mélange de BRFB. Quatorze poutres (152 x 254 x 2000 mm) sans armature transversale ajouté ont été testées sous une configuration de chargement à quatre points jusqu'à la défaillance. Les poutres ont été regroupés en deux groupes A et B en fonction de leurs rapports portée de cisaillement/profondeur, a/d. Les poutres du groupe A avaient un rapport a/d de 3,3 tandis que celles du groupe B avaient un rapport a/d de 2,5. Outre les rapports a/d, les paramètres étudiés comprenaient la fraction volumique des fibres ajoutées (0,75 et 1,5%) et le taux de renforcement longitudinal des barres en PRFB (0,31, 0,48, 0,69, 1,05 et 1,52). Les résultats des tests ont montré que l’ajout de macro-fibres de basalte au mélange de béton améliorait sa résistance à la compression. Une relation directe entre la fraction volumique de fibres, Vf, et la résistance à la compression a été observée. Les cylindres de béton coulés avec une Vf de 0,75 et 1,5% ont entraîné une augmentation de 11 et 30% de leur résistance à la compression par rapport à ceux moulés en béton standard (sans fibres), respectivement. L'ajout de fibres a également amélioré le mode de défaillance des poutres BRFB-PRFB que les poutres de contrôle coulées avec du béton standard. L’augmentation de la fraction volumique des fibres a réduit l’espacement entre les fissures et gêné sa propagation. Une amélioration significative des capacités de cisaillement des poutres testées a également été observée lorsque les macro-fibres de basalte ont été ajoutées à une fraction volumique Vf de 0,75. L'augmentation moyenne des capacités de cisaillement des poutres des groupes A et B, ayant les mêmes taux de renforcement, était respectivement de 45 et 44%, par rapport à celles des poutres de contrôle. Il a été noté que le gain en capacité de cisaillement des poutres testées était plus prononcé dans les poutres avec a/d= 3,3 que dans les poutres avec a/d = 2,5 lorsque le taux de renforcement augmentait. Au cours de la phase analytique, plusieurs modèles ont été utilisés pour prédire les capacités de cisaillement des poutres. Tous les modèles disponibles surestimaient les capacités de cisaillement des poutres testées avec un rapport moyen Vpre/Vexp compris entre 1,29 et 2,64. Cette observation a montré que ces modèles ne permettaient pas de prédire les capacités de cisaillement des poutres BRFB-PRFB. Un nouveau modèle modifié intégrant le type de renforcement longitudinal, le type de béton fibré et la densité du béton est proposé. Le modèle d’Ashour et al. -A (1992) a été modifié en utilisant un facteur égal au rapport entre le module des barres en PRF, Ef, et celui des barres en acier Es. Ce rapport prend en compte la différence de propriétés entre les barres en PRF et celles en acier, négligée par les modèles précédents. Le modèle proposé prédit bien les capacités de cisaillement des poutres BRFB-PRFB testées dans la présente étude avec des rapports moyens Vpre/Vexp = 0,82 ± 0,12 et 0,80 ± 0,01 pour les poutres des groupes A et B, respectivement. Les capacités de cisaillement des poutres en béton léger testées par Abbadi (2018) ont été prédites avec un rapport moyen Vpre/Vexp = 0,77 ± 0,05. De plus, le modèle prédit bien les capacités de cisaillement des poutres coulées avec du béton qui contient des fibres en acier testées par Awadallah et al. (2014) avec un rapport moyen Vpre/Vexp = 0,89 ± 0,07. Cela indique la large gamme d'applicabilité du modèle proposé. Cependant, il est recommandé d’évaluer le modèle proposé sur un ensemble de données plus large que celui présenté dans cette étude.This study evaluates both experimentally and analytically the shear behavior of basalt fiber-reinforced concrete (BFRC) beams reinforced longitudinally with basalt fiber-reinforced polymer (BFRP) bars. A new type of basalt macro-fibers was added to the concrete mix to produce the BFRC mix. Fourteen beams (152 x 254 x 2000 mm) with no transverse reinforcement provided were tested under four-point loading configuration until failure occurred. The beams were grouped in two groups A and B depending on their span-to-depth ratios, a/d. Beams of group A had a ratio a/d of 3.3 while those of group B had a ratio a/d of 2.5. Besides the span-to-depth ratios, the parameters investigated included the volume fraction of the fibers added (0.75 and 1.5%) and the longitudinal reinforcement ratio of the BFRP reinforcing bars (0.31, 0.48, 0.69, 1.05, and 1.52). The test results showed that the addition of basalt macro-fibers to the concrete mix enhanced its compressive strength. A direct relationship between the fiber volume fraction, Vf, and the compressive strength was observed. Concrete cylinders cast with Vf of 0.75 and 1.5% yielded 11 and 30% increase in their compressive strengths over those cast with plain concrete, respectively. The addition of fibers greatly enhanced the shear capacity of BFRC-BFRP beams compared to their control beams cast with plain concrete. The increase of the fiber volume fraction decreased the spacing between cracks and hindered its propagation. A significant enhancement in the shear capacities of the tested beams was also observed when the basalt macro-fibers were added at a volume fraction Vf of 0.75%. The average increase in the shear capacities of beams of group A and B, having the same reinforcement ratios, were 45 and 44%, respectively, in comparison with those of the control beams. It was noticed that the gain in shear capacities of the tested beams was more pronounced in beams with a/d = 3.3 than in beams with a/d = 2.5 when the reinforcement ratio increased. In the analytical phase, several models were used to predict the shear capacities of the beams. All of the available models overestimated the shear capacities of the tested beams with average ratio Vpre/Vexp ranging between 1.29 to 2.64. This finding indicated that these models were not suitable to predict the shear capacities of the BFRC-BFRP beams. A new modified model incorporating the type of the longitudinal reinforcement, the type of FRC used, and the density of concrete is proposed. The model of Ashour et al. –A (1992) was calibrated using a calibration factor equal to the ratio of modulus of FRP bars used, Ef, and that of steel bars, Es. This ratio takes into consideration the difference in properties between the FRP and steel bars, which was overlooked by previous models. The proposed model predicted well the shear capacities of the BFRC-BFRP beams tested in the current study with average ratios Vpre/Vexp = 0.82 ± 0.12 and 0.80 ± 0.01 for beams of groups A and B, respectively. The shear capacities of the lightweight concrete beams tested by Abbadi (2018) were predicted with an average ratio Vpre/Vexp = 0.77 ± 0.05. Moreover, the model predicted well the shear capacities of the SFRC beams reinforced with BFRP bars tested by Awadallah et al. (2014) with an average ratio Vpre/Vexp = 0.89 ± 0.07. This indicates the wide range of applicability of the proposed model. However, it is recommended that the proposed model be assessed on larger set of data than that presented in this study
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Gaumond, Baptiste. "Compréhension des interfaces / interphases formées dans les composites PPS / fibres de carbone et PPS / fibres de basalte réalisés à partir de mèches comélées et retordues." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI064.
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Ces travaux de thèse sont consacrés à la compréhension des relations structures-propriétés des matériaux composites réalisés à partir de mèches hybrides composées de la matrice thermoplastique, le polysulfure de phénylène et de renforts qui peuvent être soit du carbone soit du basalte. Plusieurs axes de recherche ont été approfondis dans ces travaux : i) l’impact des procédés de fabrication des mèches sur les propriétés finales des composites, ii) la compréhension des interactions fibres-matrice dans les systèmes étudiés et iii) l’optimisation de ces interactions à l’interphase. Ces travaux ont démontré le lien établi entre les propriétés mécaniques et structurelles des mèches hybrides et les propriétés finales des matériaux composites obtenus. Le procédé de comélage par air conditionne en partie les propriétés finales des composites en diminuant les propriétés mécaniques des fibres de renfort. Cette dégradation n’est pas observée pour le procédé de retordage. Dans le même temps, les composites obtenus par comélage sont de meilleure qualité en termes d’homogénéité, propriétés mécaniques et taux de porosité par rapport à ceux issus du procédé de retordage. Dans un second temps, l’adhérence de l’ensemble des systèmes étudiés a été évaluée à l’échelle micromécanique et corrélée à l’échelle macroscopique. Des essais de vieillissement accélérés ont également été conduits pour discriminer les solutions les plus durables. Une dernière partie de ces travaux est consacrée à l’optimisation des propriétés interfaciales des systèmes étudiés. Les deux voies explorées ont donné des résultats intéressants : l’utilisation d’un mélange polymère PPS / PE-EMA-GMA a permis d’améliorer jusqu’à 56 % l’IFSS avec les fibres de basalte et l’utilisation d’un sel imidazolium en tant qu’agent interfacial dans la matrice a permis d’améliorer de 25 % l’IFSS obtenu avec les fibres de carboneThis thesis work is devoted to the understanding of the structure-properties relationships of composite materials made from hybrid rovings composed of the thermoplastic matrix, polyphenylene sulphide, and reinforcements that can be either carbon or basalt. Thus, several lines of research have been pursued in this work: i) the impact of the commingling process on the final properties of composites, ii) the understanding of fiber-matrix interactions and iii) the optimization of those interactions in the interface. This work first demonstrated the link established between the mechanical and structural properties of the hybrid yarns and the mechanical properties of composite materials. The air commingling process degrades the resistance of the fibers and this is observed both on filaments tensile tests and commingled yarns. This degradation is not observed on twisted yarns. In the same time, composites based on commingled yarns show a better homogeneity, mechanical properties and a lower porosity rate. In a second step, the adhesion developped in all composite systems was evaluated at the micromechanical scale and correlated at the macroscopic scale. Accelerated ageing tests were also carried out to discriminate the most durable solutions. A final part of this work is devoted to the optimization of the interfacial properties of the systems studied. Two solutions were developed and gave interesting results: the use of a PPS / PE-EMA-GMA polymer mixture allowed to improve up to 56% the IFSS with basalt fibers and the use of an imidazolium salt as interfacial agent in the matrix allowed to improve by 25% the IFSS obtained with carbon fibers
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Zourek, Milan. "Možnosti aplikace čedičových vláken do betonu." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-372072.
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This diploma thesis deals with possibilities of application of basalt fibers in concrete and in cementitious composites. In the theoretical part there is a summary of fibers usually used for fiberconcretes. Manufacturing process of basalt fibers is described, and properties of basalt fibers are summarized. Next part deals with properties of basalt fiber reinforced concrete. Concretely fresh properties, physical-mechanical properties, shrinkage and cracking, microstructure and fire resistance. The last chapter deals with fire resistance of concrete in general. The experimental part of this diploma thesis is divided into two phases. There were two mixes of basalt fiber reinforced concrete made with basalt aggregate and one mix of concrete without basalt fibers in the first phase. Density, consistency by slump and air content were determined as fresh properties. As hardened properties density, compressive strength and flexural strength were determined. There was determined the effect of the temperatures 600 and 800 °C on density, compressive strength and outward of specimens. Also, deformation during the high temperature curing was recorded. In the second phase of the experimental part there were three mixes of cementitious composite made with basalt fibers and one cementitious composite without basalt fibers. Density was determined as a fresh property. Material was monitored during its mixing. As a hardened properties density, flexural strength and compressive strength were determined. There was determined the effect of the temperatures 600 and 800 °C on density, flexural strength, compressive strength and outward of specimens.
Books on the topic "Basalt fibre"
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Helen, Richardson, and Fibre Basket Weavers of South Australia., eds. Fibre basketry: Homegrown & handmade. Kenthurst, NSW: Kangaroo Press, 1989.
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Zhukov, Aleksey, Ekaterina Bobrova, Igor' Bessonov, and Elizaveta Mednikova. Energy efficiency of building systems. ru: INFRA-M Academic Publishing LLC., 2022. http://dx.doi.org/10.12737/1856852.
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The monograph summarizes and systematizes the results of experimental and theoretical studies of thermal insulation systems of building structures, technological facilities, transport facilities, and cold preservation.
The criterion for the effectiveness of system insulation solutions is energy efficiency as a criterion for a comprehensive assessment, including both taking into account the direct reduction of energy costs during the operation of insulation shells, and the costs of installation, maintenance of structures in working condition, evaluation of the operational resistance of materials and durability of system solutions as a whole.
Modern types of thermal insulation materials based on gas-filled plastics, foamed glass, foamed rubber and products based on mineral fibers are considered: stone wool, glass wool and glass fiber, basalt fiber.
It is intended for researchers, specialists in the field of materials science, technologists — developers of new types of thermal insulation materials and constructors, designing products from them, as well as for teachers and university students. It can be useful for a wide range of people interested in construction and energy saving problems.
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Museo Nacional Centro de Arte Reina Sofía, ed. White fire: The Kunstmuseum Basel Modern Collection. Madrid]: Museo Nacional Centro de Arte Reina Sofía, 2015.
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Santos, Aurelina Viana dos, and José Max Dias Figueira. Fibras vegetais para artesanato: Técnicas de produção de fibras de arumã, cipó ambé e tucumã. Manaus, AM, Brasil: Fundação Vitória Amazônica, 2000.
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San Francisco Crafts and Folk Art Museum. Textiles of old Japan: Bast-fiber textiles and old kasuri : [exhibition] March 8-April 28, 1985. San Francisco, Calif: The Museum, 1985.
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Katharina, Schmidt, Ursprung Philip, and Museum für Gegenwartskunst Basel, eds. White fire, flying man: Amerikanische Kunst 1959-1999 in Basel : Werke aus der Öffentlichen Kunstsammlung Basel und der Emanuel Hoffmann-Stiftung. Basel: Öffentliche Kunstsammlung Basel, 1999.
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Matthias, Bärmann, Fondation Beyeler, and Sprengel Museum Hannover, eds. Paul Klee: Tod und Feuer : die Erfüllung im Spätwerk = death and fire : fulfillment in the late work. Riehen/Basel: Fondation Beyeler, 2003.
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Vedagiri, Velpari. Strength and durability of basalt fiber and basalt-fiber cement composites. 1987.
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Bae, Jewan. Strength and alkaline durability of manganese dioxide modified basalt fiber and modified basalt fiber-cement composites. 1989.
Find full textBook chapters on the topic "Basalt fibre"
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Jasmin, J., and K. Balan. "Strengthening of Cohesionless Soil Using Basalt Fibre Geogrids." In Lecture Notes in Civil Engineering, 239–48. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-6444-8_21.
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Bulgakov, Alexey, Klaus Holschemacher, Iuliia Davidenko, and Vladimir Bredikhin. "Effects of Basalt Fibre on the Strength of Concrete." In Lecture Notes in Civil Engineering, 123–28. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-12703-8_13.
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Swathi, T., and K. N. Resmi. "Experimental Studies on Fly Ash Based Basalt Fibre Reinforced Concrete." In Lecture Notes in Civil Engineering, 25–39. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-26365-2_3.
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Xu, Yi, Jiangfeng Dong, and Qingyuan Wang. "Behavior of CFRP-Confined Basalt Fibre Reinforced Recycled Aggregate Concrete." In Lecture Notes in Civil Engineering, 901–9. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-5217-3_91.
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Iorfida, Antonio, Salvatore Verre, Sebastiano Candamano, and Luciano Ombres. "Tensile and Direct Shear Responses of Basalt-Fibre Reinforced Mortar Based Materials." In Strain-Hardening Cement-Based Composites, 544–52. Dordrecht: Springer Netherlands, 2017. http://dx.doi.org/10.1007/978-94-024-1194-2_63.
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Rama Rao, Panugalla, and Mycherla Chaitanya. "Experimental Investigation on Mechanical and Durability Properties of Basalt Fibre-Reinforced Concrete." In Recent Advancements in Civil Engineering, 329–39. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-4396-5_30.
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Görtz, S., K. Lengert, D. Glomb, B. Wolf, A. Kustermann, and C. Dauberschmidt. "Reinforcement made of Basalt Fibre Reinforced Polymer (BFRP) – Load-bearing capacity, durability and applications." In Current Perspectives and New Directions in Mechanics, Modelling and Design of Structural Systems, 1485–90. London: CRC Press, 2022. http://dx.doi.org/10.1201/9781003348443-242.
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Görtz, S., K. Lengert, D. Glomb, B. Wolf, A. Kustermann, and C. Dauberschmidt. "Reinforcement made of Basalt Fibre Reinforced Polymer (BFRP): Load-bearing capacity, durability and applications." In Current Perspectives and New Directions in Mechanics, Modelling and Design of Structural Systems, 515–16. London: CRC Press, 2022. http://dx.doi.org/10.1201/9781003348450-242.
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Abbass, Mahapara, and Gyanendra Singh. "Rice Husk Ash and Basalt Fibre-Based Sustainable Geopolymer Concrete in Rigid Pavements. A Review." In Lecture Notes in Civil Engineering, 361–72. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-6969-6_32.
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Durga Prasada Rao, V., N. V. N. Sarabhayya, and A. Balakrishna. "Study of Mechanical Properties and Thermal Conductivity of Carbon and Basalt Fibre-Reinforced Hybrid Polymer Composites." In Lecture Notes on Multidisciplinary Industrial Engineering, 725–38. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-32-9471-4_61.
Full textConference papers on the topic "Basalt fibre"
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LILLI, MATTEO, MILAN ZVONEK, VLADIMIR CECH, CHRISTINA SCHEFFLER, JACOPO TIRILLÒ, and FABRIZIO SARASINI. "PLASMA POLYMERIZATION ON UNSIZED BASALT FIBRES FOR IMPROVING THE INTERFACIAL STRENGTH WITH POLYMER MATRICES." In Thirty-sixth Technical Conference. Destech Publications, Inc., 2021. http://dx.doi.org/10.12783/asc36/35903.
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Basalt fibres are becoming a promising alternative to synthetic fibres as a green reinforcement phase in polymeric matrix composites, showing excellent mechanical, chemical and thermal properties. In this work we synthetized tetravinylsilane (TVS) or a mixture formed by tetravinylsilane and different percentages of oxygen on the surface of unsized basalt fibres through the Plasma-Enhanced Chemical Vapor Deposition (PECVD) technique for improving the fibre/matrix adhesion. Single fibre tensile test proved the effectiveness of the process, without any degradation of the mechanical properties of modified basalt fibres. Finally, through pull out tests, the interfacial properties of basalt fibres were studied, measuring increases up to 80% of the IFSS for modified fibres compared to neat fibres. This result is the consequence of a greater chemical compatibility between the fibres and the matrix, thanks to the presence of a higher number of Si-O-C groups, and of a mechanical interlocking effect promoted by the increased surface roughness of the plasma-modified fibres.
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Da Costa Santos, Ana Caroline, and Paul Archbold. "Mechanical Properties and Fracture Energy of Concrete Beams Reinforced with Basalt Fibres." In 4th International Conference on Bio-Based Building Materials. Switzerland: Trans Tech Publications Ltd, 2022. http://dx.doi.org/10.4028/www.scientific.net/cta.1.316.
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Fibre-reinforced concrete (FRC) is widely employed in the construction industry, with assorted fibre types being used for different applications. Typically, steel fibres give additional tensile strength to the mixture, while flexible fibres may be used in large sections, such as floor slabs, to control crack width and to improve the handling ability of precast sections. For many reasons, including durability concerns, environmental impact, thermal performance, etc, alternatives to the currently available fibres are being sought. This study examines the potential of using basalt fibres, a mineral and natural material, as reinforcement of concrete sections in comparison to steel fibres and plain concrete mix. Mixes were tested containing 0.5% and 1.0% of basalt fibres measuring 25mm length, 0.5% of the same material with 48mm length and steel fibres measuring 50mm by 0.05%, 0.1%, 0.15% and 0.2% of the concrete volume. For the mechanical performance analysis, the 3-point bending test was led and the fracture energy, Young’s modulus and tensile strength in different moments of the tests were calculated. When compared to the control mixtures and the steel-fibre-reinforced concrete, the mixes containing basalt had a reduction in their elastic modulus, representing a decrease in the concrete brittleness. At the same time, the fracture energy of the mixtures was significantly increased with the basalt fibres in both lengths. Finally, the flexural strength was also higher for the natural fibre reinforced concrete than for the plain concrete and comparable to the results obtained with the addition of steel fibres by 0.15%.
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Hughes, Eric, Adeyemi Adesina, Bruno Paini, Sreekanta Das, and Niel Van Engelen. "Strengthening of Concrete Beams with Basalt Fibre Reinforced Polymer." In Structures Congress 2020. Reston, VA: American Society of Civil Engineers, 2020. http://dx.doi.org/10.1061/9780784482896.041.
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Fegade, Vishal, M. Ramachandran, S. Madhu, C. Vimala, R. Kurinji Malar, and R. Rajeshwari. "A review on basalt fibre reinforced polymeric composite materials." In RECENT TRENDS IN SCIENCE AND ENGINEERING. AIP Publishing, 2022. http://dx.doi.org/10.1063/5.0074178.
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Patil, Vedang, and Sandeep Sathe. "Comparison of properties of concrete having basalt and polypropylene fibre." In INSTRUMENTATION ENGINEERING, ELECTRONICS AND TELECOMMUNICATIONS – 2021 (IEET-2021): Proceedings of the VII International Forum. AIP Publishing, 2023. http://dx.doi.org/10.1063/5.0100894.
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Velukkudi Santhanam, Senthil Kumar, Prakash Sampath, Bharani Srikanth Ponnusamy, and Mohan Bangaru. "Effect of Micro (Banana) and Nano (SiC) Fillers on Mechanical Behaviors of Basalt/Epoxy Hybrid Composites." In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-86268.
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Basalt Fibre Reinforced Polymers (BFRP) was feasibly utilized as a preferable replacement to the Glass Fibre Reinforced Polymers (GFRP) due to their superior property and behaviour. Besides, reinforcing nano and micro fillers with basalt fiber will result in even better mechanical properties. In this research study, epoxy resin was blended with Cashew Nut Shell Liquid (CNSL) hardener, it beneficial to minimize the healing period. For 50% of epoxy resin, the ratio of CNSL hardener was taken as 50%. Standard Hand lay-up technique was utilized to produce the composite structures. In addition, 20g of nano and micro fillers were mixed with each epoxy-CNSL proportion. Accordingly, both (SiC & Banana) filler reinforced composites were fabricated and cut to the ASTM standard. Finally, the result of mechanical properties such as flexural and the impact (Charpy) of silicon carbide (SiC) and banana filler reinforced samples were compared.
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Venkatraman, S., K. S. Aravind, S. Sri Sudharshan Sharma, and M. P. Jenarthanan. "Optimization of Basalt Fibre–Reinforced Polymer Composites for Minimizing Delamination Effect." In Proceedings of the Advances in Technology, Engineering and Computing A Multinational Colloquium - 2017. Singapore: Research Publishing Services, 2017. http://dx.doi.org/10.3850/978-981-11-0744-3_c17-47.
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Monni, Francesco, Enrico Quagliarini, Stefano Lenci, and Gianluca Maracchini. "Strengthening three-leaf masonry with basalt fibre: Experimental and numerical data." In INTERNATIONAL CONFERENCE OF NUMERICAL ANALYSIS AND APPLIED MATHEMATICS (ICNAAM 2016). Author(s), 2017. http://dx.doi.org/10.1063/1.4992624.
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Ramakrishnan, S., A. Selvakumar, K. R. Nandagopalan, and R. Hariharan. "A study on flexural strength of beam reinforced with basalt fibre bars." In INTERNATIONAL CONFERENCE ON MATERIALS, MANUFACTURING AND MACHINING 2019. AIP Publishing, 2019. http://dx.doi.org/10.1063/1.5117927.
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Ramakrishnan, S., A. Selvakumar, K. R. Nandagopalan, and R. Vivekanandan. "A study on shear strength of beam reinforced with basalt fibre bars (BFRP)." In CENTRAL EUROPEAN SYMPOSIUM ON THERMOPHYSICS 2019 (CEST). AIP Publishing, 2019. http://dx.doi.org/10.1063/1.5117926.
Full textReports on the topic "Basalt fibre"
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Manor, M. J., and S. J. Piercey. Whole-rock lithogeochemistry, Nd-Hf isotopes, and in situ zircon geochemistry of VMS-related felsic rocks, Finlayson Lake VMS district, Yukon. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328992.
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The Finlayson Lake district in southeastern Yukon is composed of a Late Paleozoic arc-backarc system that consists of metamorphosed volcanic, plutonic, and sedimentary rocks of the Yukon-Tanana and Slide Mountain terranes. These rocks host >40 Mt of polymetallic resources in numerous occurrences and styles of volcanogenic massive sulphide (VMS) mineralization. Geochemical and isotopic data from these rocks support previous interpretations that volcanism and plutonism occurred in arc-marginal arc (e.g., Fire Lake formation) and continental back-arc basin environments (e.g., Kudz Ze Kayah formation, Wind Lake formation, and Wolverine Lake group) where felsic magmatism formed from varying mixtures of crust- and mantle-derived material. The rocks have elevated high field strength element (HFSE) and rare earth element (REE) concentrations, and evolved to chondritic isotopic signatures, in VMS-proximal stratigraphy relative to VMS-barren assemblages. These geochemical features reflect the petrogenetic conditions that generated felsic rocks and likely played a role in the localization of VMS mineralization in the district. Preliminary in situ zircon chemistry supports these arguments with Th/U and Hf isotopic fingerprinting, where it is interpreted that the VMS-bearing lithofacies formed via crustal melting and mixing with increased juvenile, mafic magmatism; rocks that were less prospective have predominantly crustal signatures. These observations are consistent with the formation of VMS-related felsic rocks by basaltic underplating, crustal melting, and basalt-crustal melt mixing within an extensional setting. This work offers a unique perspective on magmatic petrogenesis that underscores the importance of integrating whole-rock with mineral-scale geochemistry in the characterization of VMS-related stratigraphy.
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Rocky, AMK Bahrum Prang, and Amanda J. Thompson. Production of Ecofriendly Natural Bamboo Bast Fiber and Assessment of Antibacterial Activity. Ames: Iowa State University, Digital Repository, 2017. http://dx.doi.org/10.31274/itaa_proceedings-180814-277.
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Nevøy, Anne, Lars Helle, Christina Finne, Stein Erik Solbø Ohna, Nina Helgevold, Kåre Andreas Folkvord, Jorunn Thortveit, and Hans Erik Bugge. Innovasjoner i Jærskulen: lærerprofesjon i reformtid. University of Stavanger, 2016. http://dx.doi.org/10.31265/usps.211.
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I boken Professional Capital – Transforming Teaching in Every School sier Hargraves og Fullan: “Sustainable improvement can […] never be done to or even for teachers. It can only ever be achieved by and with them (2012:45). Dette sitatet fra Hargraves og Fullan angir forskningsinnretningen i dette utviklingsprosjektet. Formålet er å studere hvordan lærere involveres, engasjeres og lærer i innovasjoner i Jærskulen. Forskningsinteressen er sentrert om utviklingsaktiviteter som er satt i verk og hvordan disse relateres til lærernes profesjonsutvikling. Basert på innspill fra utviklingsleder i Jærskulen, Mats Bryne, er prosjektet konsentrert om fire innovasjoner i jærskolesamarbeidet: - Lokal skoleutvikling med utgangspunkt i skolenes valgte utviklingsområder - Gjennomføring i videregående opplæring - Profesjonsutvikling i samspill, medskaping i samarbeid med Utdanningsforbundet - Læringsteknologi i undervisningen Felles for de fire delprosjektene er at de rapporterer om engasjerte lærere som deltar i ulike innovasjonsprosesser, lokalt på de enkelte skolene og i nettverkssamarbeid mellom skoler. I så måte synes målsettingen om at «Jærskulen har eit godt læringsmiljø med god kultur for læring» – også å gjelde for lærerne. Samtidig peker delprosjektene på utfordringer og konstruktive veier for videreutvikling av innovasjonene. Studien av lokal skoleutvikling presenteres i kapittel 1. Denne er utført av Anne Nevøy og Lars Helle og har fått tittelen «Skolenes utviklingsplaner og lærerprofesjonen». Christina Finne og Stein Erik Ohna står bak studien av «Gjennomføring i videregående skole», og denne presenteres i kapittel 2. Utforskingen av «Profesjonsutvikling i samspill» - har fått undertittelen «Utdanningsforbundet og Jærskulen ‘At det er en prosess i det hele’. Nina Helgevold og Kåre Andreas Folkvord har gjennomført studien og denne presenteres i kapittel 3. Kapittel 4 handler om læringsteknologi i undervisningen. Denne studien er utført av Jorunn Thortveit og Hans Erik Bugge, og har fått tittelen «Ipad i Jærskulen».
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Nevøy, Anne, and Stein Erik Solbø Ohna. Spesialundervisning – bilder fra skole-Norge: En studie av spesialundervisnings dynamikk i grunnopplæringen. University of Stavanger, June 2014. http://dx.doi.org/10.31265/usps.226.
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Formålet med denne studien er å utforske dette sammensatte og motstridende nåtidsbildet. Vi er på jakt etter spesialundervisningens dynamikk i grunnskolen og i videregående opplæring. Det overordna forskningsspørsmålet er: Hvordan kan spesialundervisningens dynamikk i grunnopplæringen forklares og forstås? To delspørsmål leder inn i studien: • Hvordan beskriver faggruppene i skolen økningen i spesialundervisning, og hvilke forhold mener de bidrar til økningen? • Hvilke mønstre framkommer i beskrivelsene av skolens spesialundervisning, hvilke krefter er i spill og hvilken innvirkning har disse på omfanget av spesialundervisning? Studiens empiriske materiale er framkommet gjennom intervju med fire faggrupper i skolen; lærere, rektorer, PPT og skoleeier. Disse intervjuene er gjennomført høsten 2011 i seks kommuner og to fylkeskommuner. Erfaringer og synspunkt fra faggruppene i disse kommunene og fylkeskommunene representerer et variert bilde av skole-Norge, fra nord til vest og øst, og faggruppenes meninger gir et bredt grunnlag for å utvikle kunnskap om spesialundervisningen i grunnopplæringen. Studien er konsentrert om faggruppene i skolene sine perspektiv på spesialundervisning. Spørsmål om hva elever og foreldre mener om spesialundervisning, inngår ikke i denne sammenhengen. For-målet her er å få del i meninger og refleksjoner til skolens faggrupper og det er derfor valgt en kvali-tativ tilnærming basert på fokusgruppeintervju og kvalitative analyser. Siktemålet er å forstå en kompleks del av skolens virksomhet. Studien tar derfor ikke opp kvantitative størrelser ved skolens spesialundervisning, som effekt av spesialundervisningen for enkeltelever eller omfang av spesialun-dervisning for ulike «vanskegrupper». Presentasjonen av studien er strukturert i seks delkapitler. Innledningsvis, i kapittel 1 presenteres studiens formål og forskningsspørsmålene. I kapittel 2, Inkluderende opplæring og spesialundervis-ning utdypes studiens teoretiske innramming. I kapittel 3 presenteres Forskningsprosessen. Studiens empiriske del består av to analyser. Disse presenteres i kapittel 4 og 5. I kapittel 4, Skolens spesialun-dervisning – et innenfra perspektiv fra fagfolk i åtte kommuner/fylkeskommuner presenteres en em-pirinær analyse av datamaterialet. I kapittel 5, Spesialundervisning – skolens svar på samtidens ut-fordringer vendes blikket fra et innenfra til en utenfra perspektiv. Analysen henter fram generelle forhold ved skolens spesialundervisning og hvordan disse former et samvirkende mønster. I kapittel 6, Spesialundervisning i den inkluderende fellesskolen, sammenfattes studiens svar på spørsmålet om hvordan spesialundervisningens dynamikk i grunnopplæringen kan forklares og forstås.
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Njå, Ove, and Kirsti Russell Vastveit. Norske kommuners planlegging, gjennomføring og bruk av risiko- og sårbarhetsanalyse i forbindelse med samfunnssikkerhetsarbeidet. University of Stavanger, October 2016. http://dx.doi.org/10.31265/usps.164.
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I prosjektet; «Helhetlig ROS-analyse i norske kommuner» analyserer vi hvordan kommuner utvikler, bruker og oppdaterer ROS-analyser og risikoforestillinger i sitt samfunnssikkerhetsarbeid. Det legges vekt på hvordan kommuner integrerer ROS-arbeidet og risikoforestillinger i eksisterende plan- og arbeidsprosesser. Hvilke utfordringer opplever kommunene i dette arbeidet? Etter å ha jobbet med risiko og sikkerhet i mer enn 20 år, og en vesentlig del av disse opp mot kommuner, er det etter vårt syn et gjennomgående trekk at kommunalt ansatte som jobber med sikkerhet og beredskap har stor skepsis til akademikere på dette feltet. Den teoretiske «verden» er ikke i stand til å kommunisere med den praktiske og vice versa. Denne utfordringen mener vi står sterkt også i dag, og dermed ble det i prosjektet viktig å finne ut hvordan begrepene ble brukt i kommunene. Hvor kritiske er begrepene for omfanget av bruken av analysene? Står vi ved et markant skille nå med innføring av ny veileder for helhetlig ROS-analyse i kommuner? Eller, er arbeidet omkring samfunnssikkerhet og beredskap fastnet i en praksis uten påvirkning fra ROS-analyse? Datamateriale fra 26 kommuner er inkludert i studien. Kommunene dekker alle landsdelene og de har varierte demografiske og geografiske profiler. Blant deltagerne er kommuner med storulykkesindustri, større bykommuner, mindre øykommuner og grensekommuner. Opptil fem personer med ulikt ansvar for samfunnssikkerhets- og beredskapsarbeidet er intervjuet i hver kommune. En viktig del av prosjektet er forholdet mellom ROS-analyser på ulike forvaltningsnivåer, hvordan ROS-analysene kommuniserer risikoforestillinger og hvordan kommunene kan bygge på og hente innspill fra hverandre i ROS-analysearbeidet. Siden 2010 har Lov om kommunal beredskapsplikt, sivile beskyttelsestiltak og Sivilforsvaret (sivilbeskyttelsesloven) og underliggende Forskrift om kommunal beredskapsplikt stilt krav til kommunenes ROS-analyse og samfunnssikkerhetsarbeid i stort. Likevel er det ikke opplagt hva det innebærer. Forskriften snakker om begreper og konsepter som; - Jobbe systematisk og helhetlig med samfunnssikkerhet; - Forankring i kommunestyret; - Eksisterende og fremtidige risiko- og sårbarhetsfaktorer; - Særlige utfordringer; - Langsiktige mål, strategier, prioriteringer og plan for oppfølging av samfunnssikkerhets- og beredskapsarbeidet; - Vurdere forhold som bør integreres i planer og prosesser; og - Overordnet beredskapsplan. Det stiller store krav til kommunens ansattes kunnskap og kompetanse til å fortolke hva alle disse konseptene skal bety for kommunen og hvordan ansatte skal jobbe med kravene. Her ligger kjernen av vår studie. Studien vår viser at det legges betydelig med ressurser og arbeid ned i kommuners helhetlige ROS-analyser, samfunnssikkerhets og beredskapsarbeid. Risikoinformert styring og risikotenkning er en krevende filosofi, hvor det forutsettes at de ansatte med ansvar for kommunens systemer og samfunnssikkerhets- og beredskapsarbeidet har høy kompetanse på området. I kommunene som deltok i studien synes det å være enklere for kommunene å konkretisere hvordan de arbeidet med beredskap enn med samfunnssikkerhet. Kommunene hadde i varierende grad oversikt over hvordan beredskapsarbeidet var satt i system på tvers av etater. Materialet ble analysert ut fra fire forhold: - Begrepsforståelser og bruk av begreper for å uttrykke samfunnssikkerhet - Planlegging og gjennomføring av ROS-analyseprosesser - Presentasjon av resultater fra ROS-analysearbeidet - Implementering av analyseresultatene i kommunens aktiviteter Datamaterialet viser at kommunene og de fleste respondentene våre er i liten grad bekymret over begrepene de bruker. I hovedsak er det risiko, ROS-analyse (eller andre koplinger av ROS), hendelser, akseptkriterier, beredskap, kriseplaner og tiltak som er konseptene i bruk. Usikkerhet var et begrep som fulgte med, men det var i liten grad reflektert over utover at det var en egenskap med hele ROS-analyseprosessene. Samfunnssikkerhet, ytelse av beredskapstiltak, sårbarhet, resiliens, barrierer, system er begreper som får lite eller ingen omtale i kommunenes befatning med samfunnssikkerhet og beredskap. Kommunene er veldige instrumentelle i arbeidet med å utvikle produktene (helhetlig) ROS-analyse og beredskap- og kriseplaner. Beslutningsprosessene som den helhetlige ROS-analysen er en del av, trekkes ikke frem som førende for hvordan ROS-analyser og samfunnssikkerhetsarbeidet gjøres. Fylkesmannen sin rolle som pådriver, rådgiver og tilsynsmyndighet var for de aller fleste kommunene beskrevet med positive fortegn. Alle analysene vi har hatt tilgang til er utført som grovanalyser (hazid-gjennomganger, scenariobeskrivelser, gruppediskusjoner), men med relativt små variasjoner innenfor hvordan risiko måles og uttrykkes. Enkelte kommuner inspireres av innholdet i FylkesROS-analyse eller Nasjonalt Risikobilde, mens andre har et større fokus på lokale forhold og hendelser. I forbindelse med bruk av tiltak fra helhetlig ROS-analyse var det en klar trend at kommunene synes det var vanskelig å sikre implementering av tiltak. Dette skyldes blant annet at det var utfordrende å sikre at den ansvarlige etat tok ansvar for tiltak, at beredskapskoordinatorer ikke anså tiltak som skulle implementeres i enkeltetater som sitt ansvar og at kommunene i mange tilfeller ikke hadde midler til gjennomføring av tiltak. Problemet kan trolig også spores til at helhetlig ROS-analyse ikke var et dokument som var i aktiv bruk i hverdagen til kommunenes ansatte, og som det i de fleste tilfeller ikke ble laget aksjonsplaner for å følge opp. På tiltakssiden var det også tydelig at flere kommuner gjorde det vanskelig for seg selv, ettersom de beskrev svært generelle tiltak i rapportene sine, tiltak som egentlig var på plass i den ansvarlige etat og som var dekket av andre internkontrollrutiner, eller som andre offentlige etater var ansvarlige for. Kommunene i prosjektet hadde i varierende grad koblet beredskapsplanene sine opp mot de helhetlige ROS-analysene. En annen utfordring i forbindelse med «bruk» til beredskapsplanlegging var at kommunene ikke var sikre på hvordan dette skulle tolkes. Skulle man lage øvelser basert på hendelsene som var brukt i helhetlig ROS-analyse, skulle det lages tiltakskort som passet til scenarioene i helhetlig ROS-analyse? Enkelte kommuner hadde inkludert hendelser fra helhetlig ROS-analyse i beredskapsplanverket sitt, mens andre hadde fokusert mer på felles kapasiteter i helhetlig ROS-analyse. Å se sammenhengen mellom helhetlig ROS-analyse og beredskapsplanlegging var et vanskelig tema for kommunene. Beredskapsanalyse og vurdering av «godheten» av beredskapstiltak er også en stor utfordring. Den største utfordringen og det viktigste funnet som har kommet fram gjennom studiet er at prinsippene i risikobasert styring er nærmest fraværende i kommunene. Funksjonelle krav til sikkerhet mangler, en levende diskusjon om samfunnssikkerhet og beredskap mangler, og analysene brukes i svært liten grad. ROS-analyse og intensjoner om risikobasert styring har vært i norske kommuner i mer enn 20 år, og basert på dette mener vi at det er kompetanse og reguleringsregimet det må gjøres noe med, heller enn å innføre nye veiledere og tilsynsaktiviteter. Ansvaret for kommunens samfunnssikkerhets- og beredskapsarbeid må knyttes opp mot spesifikk kompetanse. Det krever at kommunene endrer praksis på i den administrative ledelsen og virksomhetene som eier systemene, tjenestene og aktivitetene, så vel som i kommunikasjonen mellom administrativ og politisk ledelse når det gjelder samfunnssikkerhet og beredskap. Vi mener at politikeren fra bykommune 1 langs kysten i Nord-Norge illustrerer behovet på en betegnende måte: «Veldig få i beredskapsrådet har lest dokumentene. I vårt fylke tror jeg vi er noen av de som har kommet lengst, og det sier etter mitt skjønn sitt». «Vi må involvere oss på et mye tidligere stadium. Skaffe oss oversikt over hva som er beredskapsplanene, og hvor flaskehalsene er. Det tror jeg at jeg deler med veldig mange. Vi strykes med hårene i alt for stor grad. Vi får for mye ros.»
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EXPERIMENTAL STUDY ON MECHANICAL PROPERTIES AND OPTIMIZATION OF CHOPPED BASALT FIBER REINFORCED CONCRETE. The Hong Kong Institute of Steel Construction, August 2022. http://dx.doi.org/10.18057/icass2020.p.251.
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This paper investigated the influence of CBF damage mode of matrix concrete and the strength of matrix concrete under different stress states. The length of basalt fiber is 6 mm. Three basic mechanical properties tests were conducted with five fiber volume admixtures of 0.00%, 0.05%, 0.10%, 0.15% and 0.20% used as the variables. A total of 90 specimens of different sizes were prepared to study the variation rules of compressive strength, splitting tensile strength and flexural strength at different ages of 7d and 28d, the strengthening mechanism of the reinforcing effect of CBF was also analyzed, and the optimal volume fraction of CBFs was obtained. The results can be concluded that (1) the disordered distribution and uniform dispersion of CBF improve the damage morphology of concrete matrix, reflecting a good effect in the enhancing and crack-resisting; (2)The compressive strength and flexural strength increase first and then decrease with increasing of the fiber incorporation amount, and the BFRC reach their strength peak points when the fiber volume ratio is equal to 0.10%; (3) The dispersion of tensile strengths are relatively high, but they still show a trend of slow increasing trend.