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1
Zlebek, T., J. Hodul, L. Meszarosova, and R. Drochytka. "Chemical stability of innovative grouts for cast basalt elements." IOP Conference Series: Materials Science and Engineering 1039 (January 19, 2021): 012024. http://dx.doi.org/10.1088/1757-899x/1039/1/012024.
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Karthigeyan, R., and G. Ranganath. "Effect of Forging Parameters on Low Cycle Fatigue Behaviour of Al/Basalt Short Fiber Metal Matrix Composites." Scientific World Journal 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/250513.
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This paper deals with metal matrix composites (MMCs) of Al 7075 alloy containing different weight percentage (2.5, 5, 7.5, and 10) basalt short fiber reinforcement and unreinforced matrix alloy. The samples were produced by the permanent stir casting technique. The casting ingots were cut into blanks to be forged in single stage and double stage, using MN press and graphite-based lubricant. The microstructures and fatigue properties of the matrix alloy and MMC samples were investigated in the as cast state and in the single and double stage forging operations. The microstructure results showed that the forged sample had a uniform distribution of the basalt short fiber throughout the specimens. Evaluation of the fatigue properties showed that the forged samples had higher values than those of the as cast counterparts. After forging, the enhancement of the fatigue strength of the matrix alloy was so significant and high in the case of 2.5 and 5.0 wt. percentage basalt short fiber reinforced MMC, and there was no enhancement in 7.5 and 10 weight percentages short fiber reinforced MMCs. The fracture damage was mainly due to decohesion at the matrix-fiber interface.
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Popp, Ilie Octavian. "Some aspects regarding the thermic behaviour of a basalt parts in machine building industry." MATEC Web of Conferences 290 (2019): 01015. http://dx.doi.org/10.1051/matecconf/201929001015.
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This work aims to present some aspects regarding the opportunity of using basalt in manufacturing the subassemblies of machine tools. Melted and recrystallized basalt has demonstrated promising behavior with regards of its use in manufacturing, as reported in the literature. The researches presented in this work were focused on analyzing the behavior of basalt parts for machine tools submitted to thermic stress. The tests were made using grey cast iron and steel parts as reference for a comparative study. Testing methodology, specific measuring apparatus used, experimental test data records, data processing and resulting conclusions regarding the possibility of using basalt in machine tools manufacturing are presented in the paper.
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Ayub, Tehmina, Nasir Shafiq, and M. Fadhil Nuruddin. "Effect of Chopped Basalt Fibers on the Mechanical Properties and Microstructure of High Performance Fiber Reinforced Concrete." Advances in Materials Science and Engineering 2014 (2014): 1–14. http://dx.doi.org/10.1155/2014/587686.
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This paper presents the mechanical properties and the microstructure of the high performance fiber reinforced concrete (HPFRC) containing up to 3% volume fraction of chopped Basalt fibers. Three types of the concrete were prepared, out of which, the first type was prepared by utilizing 100% cement content. The other two types of the concrete were prepared by replacing 10% cement content with silica fume and the locally produced metakaolin. Using each concrete type, four mixes were prepared in which Basalt fibers were added in the range of 0–3%; that is, total twelve mixes of the HPFRC concrete were prepared. From each of the twelve concrete mixes, total twelve specimens were cast to determine the mechanical properties of the HPFRC including compressive strength (cube and cylinder), splitting tensile strength, and the flexural strength. In this way, a total of 108 specimens were cast and tested in this study. Test results showed that the addition of the Basalt fibers significantly increased the tensile splitting strength and the flexural strength of the HPFRC, while there was slight improvement in the compressive strength with the addition of Basalt fibers. The microstructure of HPFRC was examined to determine the interfacial transition zone (ITZ) between the aggregates and the paste by using field emission scanning electron microscope (FESEM), which showed the improvement of the ITZ due to the addition of the Basalt fibers.
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Pradeeba, K., and A. Rajasekaran. "Analytical Predictions on Flexural Strengthening of Reinforced Concrete Beams with Hybrid FRP Laminate." International Journal of Engineering and Advanced Technology 11, no. 1 (October 30, 2021): 15–20. http://dx.doi.org/10.35940/ijeat.a3122.1011121.
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This paper presents the predicted regression equation for the study parameters of Reinforced Concrete (RC) beams strengthened with Hybrid Fibre Reinforced Polymer (HyFRP) laminate at the soffit of beam. To study the effectiveness of HyFRP laminate on flexural strengthening a total of five beams were cast and tested.The variable parameters are thickness, elastic modulus and tensile strength of HyFRP laminates. Four combinations of HyFRP laminates precisely, 90% Glass fibre + 10% Basalt fibre of thickness, 80% Glass fibre + 20% Basalt fibre, 70% Glass fibre + 30% Basalt fibre, 60% Glass fibre + 40% Basalt fibre, and their corresponding thickness were 2.78, 3.24, 3.86 and 4.24mm respectively.The test results concluded that reinforced concrete beams strengthened with 70%Glass + 30%Basalt HyFRP laminate enhance the ultimate load carrying capacity of 68.97% with respect to control beam. The values reached through the predicted regression equation showed equitable accuracy with those of experimental values.
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Sreenatha Reddy, S., and R. Dhanasekaran. "Effect of fly ash and basalt on wrought and cast aluminum alloy." Materials Today: Proceedings 5, no. 13 (2018): 27112–17. http://dx.doi.org/10.1016/j.matpr.2018.09.018.
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Ayyanar Raja, M., V. Manikandan, P. Amuthakkannan, S. Rajesh, and I. Balasubramanian. "Wear resistance of basalt particulate-reinforced stir-cast Al7075 metal matrix composites." Journal of the Australian Ceramic Society 54, no. 1 (September 25, 2017): 119–28. http://dx.doi.org/10.1007/s41779-017-0133-8.
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Baronins, J., M. Antonov, R. Ivanov, V. Shuliak, and I. Hussainova. "Effect of basalt and silica additives on erosive wear resistance of cast ceramics." Proceedings of the Estonian Academy of Sciences 65, no. 2 (2016): 144. http://dx.doi.org/10.3176/proc.2016.2.05.
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Popp, Ilie Octavian. "Analysis of the eigenfrequencies of the basalt machine parts by the FEM." MATEC Web of Conferences 343 (2021): 08002. http://dx.doi.org/10.1051/matecconf/202134308002.
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The aim of this paper was to carry out a theoretical (numerical) scientific research on the behavior of cast and recrystallized basalt, in order to use it as a material in the manufacture of structural elements of machine tools. A unitary methodology has been established for studying the eigenfrequency of structural elements for machine tools by the finite element method. Two basalt structural elements (beam type and plate type) were modeled, which were also made physically, and with the help of the COSMOS / Mark finite element program, the eigenfrequencies of the models was studied.
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Anandakumar, R., M. S. Ravikumar, and C. Selvamony. "Mathematical Prediction for BFRP Retrofitted after Fatigue Loading of Concrete Specimens." JOURNAL OF ADVANCES IN CHEMISTRY 13, no. 10 (March 4, 2017): 5944–53. http://dx.doi.org/10.24297/jac.v13i10.5884.
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This paper deals with the experiment investigations on the Basalt Fibre Reinforced Polymer composites wrapped concrete specimens for determining the mathematical prediction for retrofitting of concrete specimens. For the past three decades, fibres are being effectively utilized in engineering fields. Some countries do not have specified codes for structural designing of Fibre Reinforced Polymer composites. Especially for this situation, the mathematical predictions were determined by experimentally for Basalt Fibre Reinforced Polymer composites retrofitted concrete. For this experiment, cubes, cylinders and prisms were cast using M30 grade concrete to analyze the characteristic strengths. The tests were carried out with and without Basalt Fibre Reinforced Polymer wrapping and retrofitted after 0%, 30%, 60% and 90% fatigue loaded or preloaded specimens. The retrofitted specimens with Basalt Fibre Reinforced Polymer wrapping, even after 90% fatigue loaded possess higher strength than conventional one. The observed readings were analyzed and mathematical prediction was developed by using readings and graphical representations. From the study, similar results were observed through experiments and mathematical predictions.
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Isnugroho, K., D. C. Birawidha, and M. Amin. "The Potentials of Improving Mineral Source Additional Values in Lampung Province – A Preliminary Study." Journal of Engineering and Scientific Research 1, no. 1 (June 18, 2019): 1. http://dx.doi.org/10.23960/jesr.v1i1.2.
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An initial research on non-metal mineral potential was conducted for stones inLampung Province. Surveys were conducted to some districts/towns in Lampung to takesample materials. Non-metal mineral chemical composition content analysis of stoneswas conducted with X-RF method. Lampung had mineral potentials of feldspar, zeolite,kaolin, and basalt of 400,500,000 m3; 18,945,000 m3; 9,750,000 m3; 419,071,833 m3respectively. These mineral source potentials were distributed in eight districts inLampung. Processing was required to improve additional values for these mineralsources, including crushing, grinding, classifying, and concentration process.Concentration improvements were required for feldspar and kaolin minerals. Wet highintensity magnetic separator process followed by froth flotation process becamesolutions to reduce high oxide iron content. Feldspar and kaolin could be used for suchindustries of ceramic, glass, paper, and refractory. Meanwhile, the zeolite mineral fromLampung could be used for agriculture, plantation, and fishery. Basalt stone wouldhave additional values when this was processed into cast basalt, fiber, and ceramiccomposite.Keywords: feldspar, kaolin, basalt, zeolite, Lampung
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Venkatachalam, G., and A. Kumaravel. "Mechanical Behaviour of Aluminium Alloy Reinforced with Sic/Fly Ash/Basalt Composite for Brake Rotor." Polymers and Polymer Composites 25, no. 3 (March 2017): 203–8. http://dx.doi.org/10.1177/096739111702500304.
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Gray cast iron is the most commonly used material in automobile brake rotors. It generates heat easily during braking which affects its mechanical properties and the Coefficient of friction varies depending on the type of material used for the brake rotor. Aluminium (Al) based metal matrix composite can be an efficient and effective braking material compared to cast iron and matrix alloy. In the present investigation, Al6082 composites were fabricated by stir casting method by varying weight percentage of reinforcements for Sample1 (Al 90% + SiC 10%), Sample 2 (Al 90% + SiC 5% + fly ash 5%) and Sample 3 (Al 90% + SiC 5% + basalt 5%). Chemical compositions, micro hardness, wear test and tensile test were performed to study the mechanical behavior of all the test specimens. The surface morphology was studied using microscopic inspection to indicate the distribution of reinforcement particles and bonding between the matrixes. Composites containing hard oxides (like SiC) are preferred for high wear resistance along with increased hardness and high temperature oxidation resistance. The result reveals that wear rates of the composite materials is lower than that of the matrix alloy and friction coefficient was minimum. Also, it improves the micro hardness and tensile strength. The addition of fly ash and basalt decreases the wear and it acquired density almost three times lower than that of gray cast iron. In this investigation, the alternate materials for automobile brake rotors with Al reinforced composites were studied.
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Shelote, Kunal M., Hindavi R. Gavali, Ana Bras, and Rahul V. Ralegaonkar. "Utilization of Co-Fired Blended Ash and Chopped Basalt Fiber in the Development of Sustainable Mortar." Sustainability 13, no. 3 (January 25, 2021): 1247. http://dx.doi.org/10.3390/su13031247.
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Excessive consumption of cement in construction materials has resulted in a negative impact on the environment. This leads to the need of finding an alternative binder as a sustainable construction material. Different wastes that are rich in aluminosilicates have proved to be a valuable material for alkali-activated product development, which contains zero cement. Alkali-activated products are claimed to be sustainable and cost-effective. In the present study, alkali-activated reinforced masonry mortar was developed using locally available industrial waste (co-fired blended ash—CBA). Appropriate mortar design is one of the key challenges as connections between two structural elements play a significant role in building construction. The mortar designed with suitable fiber reinforcement shall significantly help to enhance the fresh, mechanical, durability, and dynamic properties. Chopped basalt fibers (CBFs) obtained from basalt rock are one of the eco-efficient fibers applied as a reinforcing material. The present study checked the feasibility of novel industrial waste-co-fired blended ash (CBA) in the development of alkali-activated masonry mortar and reinforced alkali-activated mortar. In view of sustainable construction material design, the study elaborated the application of chopped basalt fibers (CBFs) in alkali-activated mortar design. The mortar cubes were cast and tested for various properties with varying percentages of chopped basalt fibers (0.5%, 1%, and 1.5%). The results suggest that developed mortars were able to achieve higher compressive strength (10–18 MPa) and flexural strength (3–3.5 MPa). Further, based on the properties of developed alkali-activated reinforced mortar, masonry prisms were cast and evaluated for the bond strengths (flexural and shear) of masonry. The optimum properties of alkali-activated mortar were found for the mix design of alkali activator to solid ratio of 0.40 and 0.5% CBF percentage. Application of CBF in CBA alkali-activated reinforced masonry mortar proved to be an efficient construction material with no cement.
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Vannan, S. Ezhil, and S. Paul Vizhian. "Microstructure and Mechanical Properties of as Cast Aluminium Alloy 7075/Basalt Dispersed Metal Matrix Composites." Journal of Minerals and Materials Characterization and Engineering 02, no. 03 (2014): 182–93. http://dx.doi.org/10.4236/jmmce.2014.23023.
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Wang, Jee-Seok, Jong-Do Kim, and Hee-Jong Yoon. "A Study on the Protecting Wall for Transferring Pipe of Waste Using Cast Basalt Tube." Journal of the Korean Society of Marine Engineering 34, no. 6 (September 30, 2010): 816–24. http://dx.doi.org/10.5916/jkosme.2010.34.6.816.
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WANG, Jee-Seok, Jong-Do KIM, and Hee-Jong YOON. "Mechanical characteristics of fused cast basalt tube encased in steel pipe for protecting steel surface." Transactions of Nonferrous Metals Society of China 19, no. 4 (August 2009): 935–40. http://dx.doi.org/10.1016/s1003-6326(08)60381-7.
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Kharun, Makhmud, Sergey Klyuev, Dmitry Koroteev, Paschal C. Chiadighikaobi, Roman Fediuk, Andrej Olisov, Nikolai Vatin, and Nataliya Alfimova. "Heat Treatment of Basalt Fiber Reinforced Expanded Clay Concrete with Increased Strength for Cast-In-Situ Construction." Fibers 8, no. 11 (November 2, 2020): 67. http://dx.doi.org/10.3390/fib8110067.
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Expanded clay concrete (ECC) is a promising structural material for buildings due to its light weight and heat- and sound-insulating properties. Adding basalt fibers (BFs) in ECC reduces its brittleness and enhances its mechanical properties. The heat treatment (HT) of BF-reinforced ECC can significantly accelerate the strength growth during cast-in-situ construction, which allows the reduction of the turnover of the formwork and the construction period, as well as leading to lower construction costs. This paper presents an HT technology for load-bearing structures, containing a BF-reinforced ECC mix and using infrared rays for cast-in-situ construction. The issue of the strength growth of BF-reinforced ECC during HT has been studied. Microsilica and fly ash were added to the ECC mix to obtain a compressive strength of more than 20 MPa. Four different mixes of ECC with chopped BFs in the ratios of 1:0, 1:0.0045, 1:0.009 and 1:0.012 by weight of cement were studied. Test specimens were heated by infrared rays for 7, 9, 11, 13, 16 and 24 h. Then, the heat-treated specimens were tested for compressive strength after 0.5, 4, 12 and 24 h cooling periods. The analysis and evaluation of the experimental data were carried out based on probability theory and mathematical statistics. Mathematical models are proposed for forecasting the strength growth of BF-reinforced ECC during cast-in-situ construction.
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Hodul, Jakub, Tomáš Žlebek, Lenka Mészárosová, Aleš Jakubík, and Rostislav Drochytka. "Adhesives for the Installation of Cast Basalt Elements on Metal and Comparison of Properties when Using Different Types of Fillers." Key Engineering Materials 898 (August 27, 2021): 35–41. http://dx.doi.org/10.4028/www.scientific.net/kem.898.35.
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The polymeric adhesives for the installation of basalt elements on a metal base are designed primarily for environments with increased chemical and mechanical stress. They are composed of polymer resins (epoxy, polyurethane) as binders, as well as organic additives and mineral admixtures that mainly fulfill the function of filler. In all sectors of today's construction industry, maximum efficiency in the production of materials is required for sustainability purposes, which, however, must never be at the expense of the quality or the required performance. Due to these requirements, great emphasis is placed on the maximum use of secondary raw materials. Talc is used as the primary filler for polymer adhesives. Sawdust, tire rubber, and fly ash are used as secondary raw materials. The use of these in building supplies can positively affect some physical and mechanical properties of polymeric adhesives. Also, the use of secondary raw materials has the above-mentioned ecological benefit. Basic properties, such as bulk density and adhesion to both metallic and basalt elements, were monitored. The details of the cohesion of the adhesive with the bonded material, as well as the distribution of secondary raw materials in the polymer matrix, were assessed microscopically.
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Pavlović, M., M. Dojčinović, Lj Andrić, and D. Radulović. "Comparison of the formation and development of cavitation damage on cast and sintered samples based on basalt." Journal of Mining and Metallurgy A: Mining 55, no. 1 (2019): 37–44. http://dx.doi.org/10.5937/jmma1901037p.
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Chandran, A., and M. Neelamegam. "Flexural Behaviour Of Strengthened RC Beams With Multi-Directional Basalt Fibre - Reinforced Polymer Composites." Archives of Civil Engineering 61, no. 1 (March 1, 2015): 45–58. http://dx.doi.org/10.1515/ace-2015-0003.
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AbstractThe paper describes an experimental behaviour of the basalt fibre reinforced polymer composite by external strengthening to the concrete beams. The BFRP composite is wrapped at the bottom face of R.C beam as one layer, two layers, three layers and four layers. The different characteristics - are studied in - first crack load, ultimate load, tensile and compressive strain, cracks propagation, crack spacing and number of cracks etc. To - investigate, total of five beams size 100mm× 160mm×1700mm were cast. One beam is taken as control and others are strengthened with BFRP composite with layers. From this investigation, the first crack load is increased depending on the increment in layers from 6.79% to 47.98%. Similarly, the ultimate load carrying - capacity is increased from 5.66% to 20%. The crack’s spacing is also reduced with an increase in the number of layers
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Zhao, Yawei, Xinjian Sun, Peng Cao, Yifeng Ling, Zhen Gao, Qibing Zhan, Xinjie Zhou, and Mushuang Diao. "Mechanical Performance and Numerical Simulation of Basalt Fiber Reinforced Concrete (BFRC) Using Double-K Fracture Model and Virtual Crack Closure Technique (VCCT)." Advances in Civil Engineering 2019 (November 11, 2019): 1–15. http://dx.doi.org/10.1155/2019/5630805.
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This paper mainly investigates the fracture parameters of Basalt Fiber Reinforced Concrete (BFRC) with various fiber lengths and dosages using Double-K fracture model. The model was developed by fracture criterion using ABAQUS Virtual Crack Closure Technique (VCCT), and the results of the model and experiments were compared. The basalt fiber with length of 6 mm and 12 mm was added into concrete in the dosage of 0.0%, 0.1%, 0.2%, 0.3%, 0.4%, and 0.5% by volume of concrete, respectively. Concrete specimens were cast into three dimensions, i.e., 60 mm × 180 mm × 480 mm, 80 mm × 240 mm × 640 mm, and 100 mm × 300 mm × 800 mm. Then, three-point bending test was conducted on precast-notched beams. The load versus cracking mouth opening displacement (P-CMOD curve) was developed in order to evaluate cracking and breaking load. The initial fracture toughness and unstable fracture toughness were derived from the Double-K fracture model aimed to optimize the fiber length and dosage. The results showed that the initial fracture toughness and unstable fracture toughness increased first and then decreased with the increase in fiber dosage, and basalt fiber with length of 6 mm and dosage of 0.2% performed the best toughening effect on concrete. The comparison results showed that numerical simulation can better simulate the initiation and propagation of BFRC fractures and achieve the dynamic propagation process of fractures.
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Alkhraisha, Hakem, Haya Mhanna, Noor Tello, and Farid Abed. "Serviceability and Flexural Behavior of Concrete Beams Reinforced with Basalt Fiber-Reinforced Polymer (BFRP) Bars Exposed to Harsh Conditions." Polymers 12, no. 9 (September 16, 2020): 2110. http://dx.doi.org/10.3390/polym12092110.
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The main objective of this study was to investigate experimentally and numerically the behavior of basalt fiber-reinforced polymer (BFRP) reinforcement exposed to a combination of ultraviolet rays, humidity, and rain. Specifically, the effects of the previously stated harsh exposure on the serviceability performance and flexural capacity of BFRP reinforced concrete beams was examined. Holding the exposure parameter constant, the study also evaluated the effects of reinforcement ratio and beam detailing on the flexural capacity and the bond-dependent coefficient (kb) of the beams. Seven beams were cast and tested, four of which were reinforced with exposed BFRP bars, two were reinforced with unexposed BFRP bars, and one specimen was cast and reinforced with steel bars to serve as a benchmark specimen. The results indicate that the kb factor was averaged to be 0.61 for all the beams. Test results also indicate that increasing the reinforcement ratio did not result in a directly proportional increase in the moment capacity. The period of exposure did not cause any significant impact on the behavior of the over-reinforced beams. Thus, a finite element model was created to simulate the impact of exposure on the behavior of under-reinforced BFRP reinforced concrete beams.
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Korniejenko, Kinga, Dariusz Mierzwiński, Roland Szabó, Nóra Papné Halyag, Petr Louda, Eythor Rafn Thorhallsson, and Gábor Mucsi. "The impact of the curing process on the efflorescence and mechanical properties of basalt fibre reinforced fly ash-based geopolymer composites." MATEC Web of Conferences 322 (2020): 01004. http://dx.doi.org/10.1051/matecconf/202032201004.
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Efflorescence is one of the limitations of the widespread use of geopolymers. This problem is caused by excess unreacted sodium oxide remaining inside materials. Unreacted sodium oxide creates white efflorescence on the surface of the produced material in the form of sodium carbonate heptahydrate Na2CO3∙ 7H2O. It decreases not only the aesthetic value of the final products, but also the mechanical properties of the material. The aim of this article is to analyse the influence of the curing method on the appearance of efflorescence on geopolymer composites reinforced by short basalt, especially on mechanical properties. Class F fly ash from the ‘Skawina’ coal-fired power plant (located in Skawina, Lesser Poland, Poland) was used as raw material for the geopolymerization process. The article compares two methods of curing: typical laboratory conditions (in the air) and samples submerged in water. Three series of fly ash-based geopolymer were cast: basalt fibres were added as 1% and 2% by weight of fly ash and one control series without any fibres. The investigation was performed using visual analysis, including microstructure investigation, and the testing of mechanical properties (compressive strength at ambient temperature) after 28 days.
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Smarzewski, Piotr. "Comparative Fracture Properties of Four Fibre Reinforced High Performance Cementitious Composites." Materials 13, no. 11 (June 8, 2020): 2612. http://dx.doi.org/10.3390/ma13112612.
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This study investigates the fracture properties of high performance cementitious composites (HPCC) with four different types of fibres and with volume fraction content 3%. The four fibres are steel hooked end (S), polypropylene crimped (PP), basalt chopped (B), and glass (G) fibres. The tests were carried out in accordance with the RILEM recommendations. In order to examine the fresh properties of HPCC the slump flow tests were performed. Twelve fibre reinforced HPCC beam specimens with notch were cast and tested using central point loading experiments. In addition, experimental tests of the compressive strength and splitting tensile strength were carried out. The test results made it possible to obtain representative fracture parameters, such as the equivalent strengths, residual strengths, and fracture energy of fibre reinforced HPCC. The S fibre specimens showed the best performance in terms of workability, compressive strength, tensile splitting strength, and fracture energy at large deflection. On the other hand, G fibre specimens exhibited the best performance in terms of flexural strength, equivalent flexural strength at higher deflection, and residual flexural strength at lower deflection. In terms of equivalent flexural strength at lower deflection and residual flexural strength at higher deflection, basalt fibre specimens performed the best. On the contrary, polypropylene fibre reinforced beam specimens revealed the highest deflection capacity.
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Mohammad Jani, Noraniza, Mohammad Shakir Nasif, Nasir Shafiq, and Ian Holt. "Experimental Investigation on the Effect of Varying Fiber Mix Proportion on the Mechanical and Thermal Performances of Fiber-Reinforced Self-Compacting Concrete under Hydrocarbon Fire Condition." Applied Sciences 10, no. 13 (July 2, 2020): 4586. http://dx.doi.org/10.3390/app10134586.
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This paper presents the experimental analysis of the effects of simulated hydrocarbon fire exposure on the mechanical properties and the heat transmission in fiber-reinforced self-compacting concrete, FR-SCC. For that purpose, 300-mm thick, and 1200-mm square-shaped slabs were cast. Basalt and polyvinyl alcohol (PVA) fibers were added using the content of 1, 1.5, and 2% in self-compacting concrete. For investigating the heat transmission within 300-mm thick slabs, five external thermocouples were installed at the unexposed face to the fire of the slabs. Similarly, eleven internal thermocouples were installed at an interval of 25 mm throughout the slab thickness. It has been found that fibers have shown better insulation than the controlled concrete; the unexposed to fire surface of FR-SCC showed temperatures lower by ten degree Celcius than the controlled concrete. Compressive strength results showed that fiber addition caused a higher reduction in strength because of softening and stiffness reduction due to high-temperature exposure. After 120 min of fire exposure, basalt fibers caused an average reduction of 30% in the compressive strength, and PVA fibers caused an average reduction of 25%. Whereas, the addition of fibers improved the split cylindrical tensile strength even after exposure to 120 min of fire exposure in comparison with the unreinforced samples.
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Ramaswamy, Anandakumar, Selvamony Chachithanantham, and Seeni Arumugam. "Performance of BFRP Retrofitted RCC Piles Subjected to Axial Loads." Advances in Materials Science and Engineering 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/323909.
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This paper deals with the behaviour of basalt fibre reinforced polymer (BFRP) composites retrofitted RCC piles subjected to axial compression loads. Currently the awareness of using FRP increases rapidly in engineering fields and also among public. Retrofitting becomes vital for aged and damaged concrete structures, piles, and so forth, to improve its load carrying capacity and to extend the service life. The load carrying capacity of piles retrofitted with basalt unidirectional fabric was studied experimentally. 15 nos. of RCC end bearing pile elements were cast with same reinforcement for axial compression experiment. Three piles were used as conventional elements, another 3 piles were used as double BFRP wrapped pile elements, and remaining 9 piles were used as retrofitted piles with BFRP double wrapping after preloaded to 30%, 60%, and 90% of ultimate load of conventional element. The effects of retrofitting of RCC pile elements were observed and a mathematical prediction was developed for calculation of retrofitting strength. The stress vs. strain relationship curve, load vs. deformation curve, preloaded elements strength losses are tabulated and plotted. Besides, crack patterns of conventional elements and tearing BFRP wrapped elements were also observed. The BFRP wrapped elements and retrofitted elements withstand more axial compressive load than the conventional elements.
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Vinotha Jenifer, J., and D. Brindha. "Development of hybrid steel-basalt fiber reinforced concrete – in aspects of flexure, fracture and microstructure." Revista de la construcción 20, no. 1 (2021): 62–90. http://dx.doi.org/10.7764/rdlc.20.1.62.
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The conventional concrete is considered to be critical in various constructional applications due to its setbacks such as service load failures, brittle property, low ductility and low tensile capacity. Apart from the natural bridging mechanism (aggregate bridging), an additional bridging mechanism is necessary to overcome the existing setbacks in plain cement concrete. Thus concrete with one or more types of fibers in suitable combinations can augment the mechanical performance of concrete causing a positive synergy effect. Along with the two control mixes with and without copper slag as partial replacement of fine aggregate, two different groups of hybrid combination of fibers such as steel and basalt were cast with 3 different groups of coarse aggregate proportions of sizes 20 mm and 12.5 mm. The hybridization of fibers is assessed in this study under compression, tension, flexure and fracture. Stress-strain data were recorded under compression to validate the strain capacity of the mixtures. The mechanical properties were analyzed for the positive hybrid effect and the influencing factors were copper slag, hybrid fiber combination and coarse aggregate proportions. The optimum volume fraction of fibers and mix proportions were highlighted based on various behaviors of concrete. Steel as macro fibers and basalt as microfibers were examined under microstructural studies (SEM and EDX). The results from the flexural toughness showcased the potential of hybrid fibers with greater energy absorption capacity ensuring the ductile property of the proposed hybrid fiber reinforced concrete.
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Melichar, Jindřich, Jakub Hodul, Kamila Bergerová, and Rostislav Drochytka. "Development of New Adhesives with Share of Secondary Raw Materials for Depositing of Non-Absorbent Facing Elements in Aggressive Environments." Key Engineering Materials 808 (June 2019): 82–87. http://dx.doi.org/10.4028/www.scientific.net/kem.808.82.
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The main focus of this paper is research and development of new adhesive materials which will be possible to apply and withstand conditions of environments with exposure to aggressive chemical compounds. These new materials will also be required to withstand high temperatures up to 100°C. Main application of developed adhesives will be during laying of non-absorbent tiles mainly made from cast basalt. Several secondary raw materials were considered during the development of new adhesive mixtures as possible replacement of silicate filler components of new materials. The goal is to develop a new adhesive material with properties as close as possible to the highly durable non-absorbent elements used in stressed environments, mainly because the material will be also used for pointing between individual elements.
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Gao, Peng, Ji Wen Zhang, and Yong Ming Tu. "Experimental Study on Structural Performance of a Novel Integral Noise Barrier for Urban Rail Transit." Advanced Materials Research 163-167 (December 2010): 1905–9. http://dx.doi.org/10.4028/www.scientific.net/amr.163-167.1905.
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A novel integral noise barrier (INB) composed of steel fiber reinforced cementitious composite (SFRCC) and basalt fiber reinforced plastic (BFRP) is put forward in this paper. Compared with traditional noise barrier, INB integrated sound-absorbing panel, H type steel, autoclaved lightweight concrete (ALC) bridge guardrail panel into a whole. The basic design idea and experimental method for INB are described. Based on the engineering demand for eastern extension project of the No.2 subway line of Nanjing, six specimens were cast and tested under simulated positive and negative loads. Under the design loads, six specimens did not crack and the lateral displacement on the top of the slab is less than H /250, where H is the height of INB. The experimental results show that INB can meet the design requirements of eastern extension engineering of the No.2 subway line of Nanjing.
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Felix-Henningsen, Peter. "Field Trip D (27 September 2018): characteristics and development of the Mesozoic–Tertiary weathering mantle and Pleistocene periglacial slope deposits in the Hintertaunus mountainous region." DEUQUA Special Publications 1 (August 20, 2018): 53–77. http://dx.doi.org/10.5194/deuquasp-1-53-2018.
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Abstract. The Devonian slates and sandstones of the Rhenish Massif were subject to deep and intensive weathering under (sub)tropical climate conditions during the Cretaceous, the Paleogene and the Neogene, which caused the development of a weathering mantle (regolith) >100 m thick, consisting of kaolinitic saprolite and paleosols as well as correlated sediments. Especially the tectonic uplift of the Rhenish Massif and climate change during the Neogene and the Pleistocene led to a vast denudation of the weathering mantle. Only in less uplifted areas of the mountainous region did thick remnants of saprolites remain, and they were covered by Neogene sediments as well as Quaternary periglacial slope deposits. As the kaolinitic weathering products serve as raw materials for the clay industry, unique exposures are available in the Hintertaunus which offer impressive insights into the landscape development of the past ∼80 million years: the excursion proceeds from Giessen to Limburg and further south and southwest to the eastern and western Hintertaunus area. At site 1 near the village of Langhecke, characteristics and properties of the fresh, unweathered slates will be demonstrated. Excursion sites 2 and 3 are situated near the village of Eisenbach. In two open-cast clay mines, both a terrestrial and a semi-terrestrial saprolite from silt slate, covered by periglacial layers, are exposed. Properties and genesis will be discussed on the basis of morphological characteristics and mineralogical and geochemical analyses, as well as isovolumetric elemental mass balances. At site 4 a former basalt quarry near the village of Biebrich exposes a Paleogene Plinthosol above saprolite. The autochthonous paleosol was preserved below Upper Oligocene basalt tuff and periglacial layers. Site 5 is situated within a huge pit for mining of Upper Oligocene to Miocene quartz gravel near the village of Wasenbach. A Miocene Plinthosol developed from alluvial sediments on top of the gravel beds and was covered by periglacial slope deposits. At nearly all sites the basal layers of the periglacial cover beds consist of kaolinitic paleosol/saprolite material, which has an important influence on the site properties of the Holocene soils.
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Ilina, Lilia V., Lubov V. Zavadskaya, and Anastasia I. Ilina. "Investigation of Composition and Technological Parameters of Highly Porous Gypsum Products Obtaining." Solid State Phenomena 299 (January 2020): 130–36. http://dx.doi.org/10.4028/www.scientific.net/ssp.299.130.
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A highly porous structure of a gypsum product creation is possible due to the porisation of gypsum mass, using new types of complex gas-forming components. At the same time, it is necessary to determine the technological conditions for the optimal formation of porous gypsum products structure and methods for increasing their strength. The article proposed to use dispersed calcium carbonate and aluminum sulphate, which interaction is the reaction with the release of СО2 for the porisation of the gypsum cast mixture. Micro-reinforcing additives, such as polymeric, basalt and glass fibers were introduced into gypsum composition together with building gypsum and finely ground calcium carbonate to improve the physico-mechanical properties of gas-gypsum. The best results were shown by the gas-gypsum, which included fiberglass. Glass fiber was pre-ground to a specific surface of 190-240 m2 / kg, in order to improve further the physico-mechanical properties of gas-gypsum.
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Zhang, Yurong, Chaojun Mao, Jiandong Wang, Yanhong Gao, and Junzhi Zhang. "Sustainability of Reinforced Concrete Beams with/without BF Influenced by Cracking Capacity and Chloride Diffusion." Sustainability 12, no. 3 (February 2, 2020): 1054. http://dx.doi.org/10.3390/su12031054.
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Concrete’s production causes pronounced environmental impacts. It is confirmed that adding basalt fiber (BF) into concrete can improve the mechanical properties and reduce the chloride diffusion coefficient of concrete. Moreover, research on the environmental impact of BF and its application in concrete has gradually emerged in recent years. However, there is little research on the chloride diffusivity of concrete structures with BF under the coupling interaction of external loads and chloride action. Therefore, at first, six beams were cast to obtain the depth-dependent chloride diffusivity of concrete under the coupling interaction of chloride penetration and 50% and 80% of the cracking capacity. Then, a functional unit (FU) combining durability, cracking capacity and volume was proposed to evaluate the sustainability of the concrete structure. In addition, three extra FUs (volume, considering volume and cracking capacity simultaneously and considering volume, cracking capacity and durability simultaneously) were also proposed and compared with the first FU. Results indicate that, regardless of the applied load level, the average chloride diffusion coefficient of a reinforced concrete (RC) beam with BF is larger than that of an ordinary RC beam. Moreover, the sorting of life cycle assessment (LCA) results will vary significantly with the different preset functional units. When taking the cracking capacity into consideration, adding BF into concrete is a suitable solution to improve the sustainability of RC beams.
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Campanini, Davide, Houman A. Hadad, Christian Carloni, Claudio Mazzotti, and Antonio Nanni. "Mechanical Characterization of SRG Composites According to AC434." Key Engineering Materials 817 (August 2019): 458–65. http://dx.doi.org/10.4028/www.scientific.net/kem.817.458.
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In the last decades, technologies and materials such as fiber reinforced polymer (FRP) have been used to strengthen different types of existing structures. More recently, composites have been developed consisting of reinforcement fabrics embedded in an inorganic mortar. These composites are known as fabric reinforced cementitious matrix (FRCM), when the fabric is made of aramid, glass, basalt, polyparaphenylene benzo-bisoxazole (PBO) or carbon fibers, and steel reinforced grout (SRG), when the fabric is made of twisted high-strength steel cords. In the United States, the characterization of FRCM/SRG systems is conducted in accordance to Acceptance Criteria AC434. According to AC434, the tensile properties of FRCM/SRG are obtained through a direct tensile test on coupons using clevis grips.The objective of this research is to discuss the applicability of the AC434 test method to determine the mechanical properties of SRG as a function of the length of the anchoring plates. SRG panels were cast and stored in a humidity chamber. After a 28-day curing period, they were cut to size and metal plates of different lengths adhered to their extremities. Results show that not all the assumptions currently made in AC434 are applicable to this type of composite. The experimental response was characterized by a trilinear stress-strain behavior. Furthermore, the cracked modulus calculated based on stress values between 60 and 90% of the ultimate stress does not accurately represent reality. Re-evaluation of this provision is of importance since the cracked modulus is used in design.
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Basaran, Bogachan, Harun Yaka, and Ilker Kalkan. "Engineering plastic gripping mechanism for tension testing of FRP bars." Journal of Composite Materials 54, no. 28 (June 17, 2020): 4427–40. http://dx.doi.org/10.1177/0021998320933658.
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A new grip adaptor, made of an engineering plastic Cast Polyamide 6 (PA6G), was developed for tension testing of FRP reinforcing bars. The new adaptor offers several advantages over conventional anchors, including the ease of application and reuse, being economical, no need for skilled labor, smaller difference between the hardness of the adaptors and sample. Bars with three different diameters (6, 8 and 12 mm), three types of fiber (Carbon, Glass and Basalt) and four types of surface texture (ribbed, wound, fine-sand coated and coarse-sand coated with widely-spaced wrapping) were tested to failure under uniaxial tension. Two identical bars were tested for each combination of parameters (fiber type, surface texture and bar diameter), one with PA6G and the other with grout-filled steel anchors. The tests indicated that the proposed method was able to ensure FRP bars to reach their tensile capacities and fail by rupture without crushing in the gripping regions and pull-out from the jaws of the testing machine. The modulus of elasticity, tensile strength and ultimate strain values of the bars with PA6G anchors were in rather close agreement with the respective values of specimens with conventional steel anchors. This close agreement, i.e. mostly a difference below 5%, implies the success of the proposed method. Among all tested bars, only the ribbed ones failed in the gripping regions in the presence of both anchors as a result of the limited contact surface (rib area), pointing out the need for the use of longer anchors for ribbed bars.
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Sharma, Vikas, and Amitabh Goel. "Case of Bilateral MCA Infarct following Basal Ganglia Hemorrhage: A Rare Coincidence Case Report." International Journal of Neurology and Neurosurgery 10, no. 3 (2018): 280–82. http://dx.doi.org/10.21088/ijnns.0975.0223.10318.24.
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Larsen, L. M., W. S. Watt, and M. Watt. "Geology and petrology of the Lower Tertiary plateau basalts of the Scoresby Sund region, East Greenland." Bulletin Grønlands Geologiske Undersøgelse 157 (January 1, 1989): 1–164. http://dx.doi.org/10.34194/bullggu.v157.6699.
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The early Tertiary plateau basalts in East Greenland are situated on a continental margin and were erupted during continental break-up and initiation of sea-floor spreading in the North Atlantic. In the region stretching from Scoresby Sund southward to 69°N 40 000 km2of basalts with an average thickness of 1.5 km have been investigated by measuring and flow-to-flow sampling of 130 profiles, followed by major element geochemical analysis and microprobe analysis, trace element analysis and some Sr isotope data. The basalts rest on Mesozoic sediments in the east and on Precambrian gneiss in the west. Six basalt formations are defined: the Magga Dan, Milne Land and Geikie Plateau Formations form a lower regional sequence erupted in one volcanic episode from sites in the NW part of the region; the Rømer Fjord and Skrænterne Formations form an upper regional sequence erupted in a subsequent volcanic episode in which eruption sites moved SE to centres east of the present Atlantic coast; the Igtertivâ Formation and a coast-parallel dyke swarm formed in a third volcanic episode only recorded at the Atlantic coast. The lavas are essentially flat-lying; a narrow strip along the Atlantic coast is extensively block faulted. Single lava flows are extensive (max. 11 000 km2) and voluminous (max. 300 km3). They are well preserved, with metamorphism of the low zeolite facies. All the lavas and most of the dykes are fractionated tholeiitic basalts with Mg/(Mg+Fe2+) ratios of 0.66-0.39 and TiO2 = 1.2-4.5%. The major part (the 'main basalts', 96% by volume) have Mg ratios of 0.56-0.39, while only 4 vol.% are Mg-rich basalts with Mg ratios of 0.66-0.57. A nephelinitic tuff layer occurs at the base of the second sequence. A few dykes are alkaline. The Mg-rich basalts have microphenocrysts of olivine (FO90-70) and chromite, while the main basalts comprise both aphyric and porphyritic sequences. Phenocrysts of plagioclase (An88-37) are abundant, of olivine (FO80-57) are sparse but ubiquitous, and of augite (FS9-20) sparse and often absent. Groundmass phases are olivine (to FO3737), plagioclase (to An13, augite (to FS62), pigeonite (Fs26-50), titanomagnetite and ilmenite. All rocks contain several per cent fine-grained mesostasis. The phenocrysts frequently show disequilibrium textures and a wide range of compositions within one sample. Extrusion temperatures are calculated to 1280-1110°C, and densities to 2.68-2.78 g/cm3, increasing with fractionation. The volcanic episodes are demonstrated in systematic compositional variations with height in the basalt sequence. Each of the two major episodes started with a variety of lava compositions including Mg-rich basalts, followed by a thick sequence of 'main basalts' showing a systematic decrease of TiO2 and other incompatible elements with height, and ending with a reversal to higher TiO2 values. The third episode is not cyclic, and its products have changed incompatible element ratios. The Mg-rich basalts comprise depleted MORB type basalts, relatively enriched olivine tholeiites, and very enriched tholeiites (Mikis type basalt). Sr isotopes show 87Sr/86Sr ratios of 0.7034 in most basalts and 0.7045 in the Mikis type basalt, while some Si-rich basalts have ratios up to 0.7079. The East Greenland basalts are 'initial rifting' basalts very similar to those in Deccan. The magmas have equilibrated at low pressures in crustal magma chambers. The main basalts have fractionated ol + pl + cpx no matter whether they are aphyric or porphyritic. Simple crystal fractionation can account for sub-trends but not for the complete compositional variation of the main basalts. This is considered as resulting from fractionation in open magma chambers which were repeatedly filled, mixed and tapped. The decrease in TiO2 with height in each volcanic episode indicates increasing magma input rate and shorter residence time in the chamber, while the final reversal indicates the decline and cessation of activity. There is evidence for widespread crustal contamination (1-4%) in the magma chambers of the two lowest formations. Crustal contamination of magmas on the way to the surface occurred sporadically throughout both sequences. One case of magma mixing occurred when a Mg-rich basalt magma invaded the regional main basalt magma chamber. The Mg-rich basalts cannot be directly related to each other or to the main basalts. A petrogenetic scheme is suggested where the Mikis type basalt originated in, or contains an addition from, an undepleted or enriched mantle source. All the other magma types originated in a depleted mantle source by varying degrees and possibly depths of melting. Increasing degrees of melting are indicated for the types nephelinite - enriched olivine tholeiite – main basalt parent – MORB type basalt. The MORB type basalt may also be produced by melting of a residuum. The basalts of the third volcanic episode include another component of mantle or basaltic crust. The three recorded volcanic episodes are related to rifting events during the break-up of the North Atlantic continent, viewed as repeated attempts to straighten out a bend in the original line of opening. The two first rifting events failed while the third for a short while produced oceanic crust. Compared to other regions of the North Atlantic volcanic province the Scoresby Sund basalts are similar to basalts from Kangerdlugssuaq, northern East Greenland, West Greenland, the Faeroes, the Vøring Plateau and some basalts on lceland. The main magma source for the North Atlantic province was similar to that of the lceland hotspot, but enriched subcontinental lithosphere may also have participated in the stage of initial rifting. A correlation for the volcanic episodes throughout East Greenland and the Faeroes is proposed.
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Steenland, N. C. "On: “A Case Study of Integrated Hydrocarbon Exploration Through Basalt,” by Robert Withers, Dwight Eggers, Thomas Fox, and Terry Crebs (November 1994 GEOPHYSICS 59, p 1666–1679)." GEOPHYSICS 61, no. 3 (May 1996): 914. http://dx.doi.org/10.1190/1.1444016.
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This paper describes geophysical exploration in northern Oregon, an area covered by the Columbia River Basalt Group (CRBG) on the surface. Obtaining geophysical results through these basalts is a major problem. Magnetic, gravity, seismic, MT and subsurface data are utilized.
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Moore, James C., and Marie D. Jackson. "Observations on the structure of Surtsey." Surtsey research 14 (June 2020): 33–45. http://dx.doi.org/10.33112/surtsey.14.3.
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Comparison of investigations of the 1979 and 2017 cored boreholes coupled with continued observations of the dynamic surface of Surtsey has modified our concepts of the subsurface structure of the volcano. A geometrical analysis of the 2017 vertical and inclined cores indicates that near-surface layering dips westerly, indicating that the boreholes are located inside the Surtur crater. In subaerial deposits, as well as in deep deposits below sea level and below the pre-Surtsey seafloor, there are zones of porous tuff that contain abundant pyroclasts with narrow rims of fine ash. These features, typical of near-surface deposits, could have been carried down the vent by downslumping during fluctuating explosive activity. They support the hypothesis that a broad diatreme underlies the Surtur vent. No major intrusions were encountered in the 2017 drilling except for coherent basalt in deep sub-seafloor deposits below the center of Surtur crater. The 2017 borehole temperature measurements indicate that the peak temperature in the vertical boreholes was 124 °C at 105 meters below the surface (m.b.s.) and that in the inclined hole it was 127 °C at 115 m.b.s. immediately after drilling. These peak temperatures are 72 meters apart horizontally yet closely resemble each other in shape and magnitude, suggesting a broad heat source. In addition, measurements in the inclined hole from 200 to 290 m.b.s. indicate a temperature of 60±2 °C. This is apparently residual heat from the volcanic action that created the diatreme. These facts cast doubt on the previous concept that the heat anomaly in the 1979 borehole was due to a nearby intrusion. Instead they suggest that heat would have been conducted down from the 85-meter-thick hot lava shield within the Surtur crater into a warm diatreme substrate containing original volcanic heat. As the conducted heat moved down into the water-saturated substrate it would have elevated the temperature above the boiling point curve, baked out water, and created a vapor-dominated system below sea level. Eventually loss of heat by boiling and rise of steam caused the vapor-dominated system to retreat upward. The resulting steam rose and warmed the tephra adjacent to the lava shields where it produced broad areas of palagonitized tuff.
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SHARMA, DR VISHAL, DR N. M. KADRI DR. N. M. KADRI, DR CECIL PARMAR, DR MITESH CHANDARANA, DR INDRESH DIXIT, DR SWATI TRIVEDI, and DR KARAN DESAI. "A Case Report of Basal Ganglia Calcification - A Rare Finding of Hypoparathyroidism." International Journal of Scientific Research 3, no. 2 (June 1, 2012): 379–80. http://dx.doi.org/10.15373/22778179/feb2014/123.
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He, Hua Nan, and Wei Dong. "Study on Damaged Reinforced Concrete Beams Strengthened with Basalt Fiber Polymer Sheets." Advanced Materials Research 446-449 (January 2012): 2941–44. http://dx.doi.org/10.4028/www.scientific.net/amr.446-449.2941.
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In practical concrete structures, once reinforced concrete beams serve in case of over cracking or are even damaged due to sudden overloading, it is necessary to repair or strengthened the damaged members for purpose of restoring the structural capacities and keeping the structures working well. At present FRP strengthening technique is one of the most accepted methods available in civil engineering. This paper particularly presents a new FRP material，basal fiber, which is applied to strengthen flexural behaviors of reinforced concrete beams suffering from different amplitudes of cracking damage. Herein, total 4 reinforced concrete beams were tested including one reference beam and three beams strengthened with basalt fiber polymer sheets. The three strengthened beams were preloaded to an expected load and then strengthen by basalt fibers under loading. The test parameters are involved in different pre-loads and layers of basalt fiber sheets. During test some flexural behaviors were obtained in terms of variation of strain in concrete, steel bar and basalt fiber sheet, flexural deflection, collapse loads and the failure modes as well as cracking properties of R.C beams strengthened with basalt fiber sheets. The results of test indicated that flexural behaviors of the beams strengthened under loading with basalt fiber polymer could be improved in different degree with varied initial flexural moment and numbers of basalt fiber.
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Bensaida, Lamiaa, Sarah Sabur, Samir Mazouz, Noureddine Gharib, and Abdellah Abbassi. "Extensive perianal basal cell carcinoma: a case report." International Journal of Medical Reviews and Case Reports 2, Reports in Surgery and Dermatolo (2019): 1. http://dx.doi.org/10.5455/ijmrcr.extensive-perianal-basal-cell-carcinoma.
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Hoareau, Jean-Luc, Eric Nicolini, Bertrand Fritz, and Eric Delcher. "Geochemical signatures of underground waters in a basaltic tropical environment. Experimental approach." Bulletin de la Société Géologique de France 176, no. 3 (May 1, 2005): 257–67. http://dx.doi.org/10.2113/176.3.257.
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Abstract Introduction The Reunion Island is an oceanic basaltic island (2500 km2) located in the Indian Ocean under tropical climate (fig. 1). It comprises two shield volcanoes (i) the Piton des Neiges (3069 m omsl), active between 2.1 Ma and 12,000 y and now inactive; (ii) the Piton de la Fournaise (2631 m omsl), active still 1 Ma. This volcanic system presents the complete alkaline magmatic series from the most alkaline end-members to the most differentiate ones: oceanite, aphyric basalt, cotectic basalt, zeolitic basalt, plagioclase-rich basalt and mugearite (fig. 2). The humid climate, with a maximum annual rainfall around 12,000 mm on the eastern coast, favours an intense weathering of rocks and probably the formation of impermeable deep levels in the massif [Courteaud et al., 1997], originating a large number of springs in altitude. The chemical composition of these spring waters indicates a variable chemical signature as a function of the lithology of the concerned drainage basins [Join et al., 1997; Hoareau, 2001] : the Mg/Ca ratio in natural waters is respectively 0.3 and 4.3 for plagioclase-rich basalt aquifer and oceanite aquifer (tab. I). This study is therefore devoted to an experimental approach of the origin of these geochemical signatures. Method Experimental weathering was conducted in double, in closed systems (batch) during 200 hours per experiment, at 20oC, using pure water (750 ml). The reacting rock samples had a given parallelepipedic shape (12 mm x 3 mm x 57 mm) and represented the six types of basalts mentioned above for the complete magmatic differentiated series (fig. 2). CO2 gas was bubbled through each reactor in order to simply reproduce (i) natural conditions in soils or (ii) possible deep CO2 contaminations [Nicolini et al., 1991], without studying in detail the effect of a variable CO2 partial pressure. The aqueous samples were collected during each experiment when a significant variation of electrical conductivity was detected. Results The analytical results clearly show that each type of basaltic rock produces in the aqueous reacting fluid a specific geochemical signature (fig. 4b). This signature reflects first the mineralogical composition of the weathered rock and secondly the distribution of the chemical elements in the different mineral phases of the rocks (particularly between crystalline or vitreous phases). The aqueous solutions produced by experimental weathering reach the domain of composition of natural waters, having altered similar rocks, after about thirty five hours when they reach a quasi steady state of concentration for major cations and anions (fig. 3), while the silica concentration still increases (fig. 5). Discussion The intensity of weathering, illustrated first by the electrical conductivity of natural waters (fig. 3), decreases significantly in the following order of reacting basalts: mugearite (112 μS.cm−1), zeolitic basalt (90 μS.cm−1), cotectic basalt (40 μS.cm−1), and the three remaining basalts (30 μS.cm−1). This gives an idea of the total salts (TDS) dissolved by experimental weathering. The potential weathering sequences have been confirmed by a geochemical modelling of the basalt-water interaction [Hoareau, 2001] using a computer code based on thermodynamic options [the KINDIS code, Madé et al., 1994] without using here kinetic laws not enough documented for basaltic rock-forming minerals. These results allowed to suggest what are the possible geological environments for the underground major water circulation pathways, deduced from the characteristics of natural solutions in springs on the volcano. Such an approach can also be used as an indirect prospecting approach of the geology of aquifers in complex geological environments, sometimes very difficult to approach in the field of the Reunion Island, because of their depth. Conclusion The experimental weathering of basaltic rocks representative from the basaltic underground environments in the Reunion Island has shown interesting results: – the hydrolysis seems to be more important in differentiated basalts. As an example, mugearite alteration produced the solutions with the highest total dissolved salts (TDS); – the transfer of sodium and potassium from basalts to solutions is highest when these elements are located in the crystals (fig. 6) more than in the glass fraction. In this way the percentage of sodium in plagioclasic rich basalt (crystal) reaches 16.43% and only 10.86% in the lixiviating solution. In the case of mugearite (glass fraction) the percentages are respectively 42.88% and 5.21%; – the extraction of calcium and magnesium from the basalts is the highest when these elements are located in the vitreous part (mesostase) of the rock, as in mugearite and oceanite (fig. 6). The results underline the fact that the ability of a rock to liberate some elements is strongly related to its petrology. This study also allows to precise more in detail the geochemical signature of the solutions produced by weathering of the basalt as a function of the basalt-forming mineral phases for a given type of basalt : the differentiation of rocks and the proportion of phenocrysts, microlites and glass play obviously an important role in the control of the chemical composition of weathering solutions. Basalt dissolution is clearly incongruent and dependent on the distribution of chemical elements in the different phases of the rock: (glass, mesostase, crystals) as shown by Crovisier et al. [1990] and Legal [1999]. The comparison between computed chemical compositions of weathering solutions (fig. 4b) and compositions of natural spring waters (fig. 4d) is very encouraging and validate the geochemical model for the interpretation of these geochemical signatures, even without using kinetic laws in a first approach. However some discrepancies still exist, probably due to the fact that the reacting rocks in the experiments represent only one type of basalt, while the natural solutions are generally reacting with different types of basalts in complex hydrogeological systems in large drainage basins. The study of these mixing phenomena is now an interesting perspective for future studies. This study may also be completed using geochemical computer codes combining thermodynamic and kinetic approaches of solutions-basalts interactions in coupled mass-transfer models. This is now under development.
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Gallagher, Joseph W., and Peter W. Dromgoole. "Exploring below the basalt, offshore Faroes: a case history of sub-basalt imaging." Petroleum Geoscience 13, no. 3 (August 2007): 213–25. http://dx.doi.org/10.1144/1354-079306-711.
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Reshef, Moshe, Haim Shulman, and Zvi Ben-Avraham. "A case study of sub-basalt imaging in land region covered with basalt flows." Geophysical Prospecting 51, no. 3 (May 2003): 247–60. http://dx.doi.org/10.1046/j.1365-2478.2003.00368.x.
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Lagabrielle, Yves, Alain Chauvet, Marc Ulrich, and Stéphane Guillot. "Passive obduction and gravity-driven emplacement of large ophiolitic sheets: The New Caledonia ophiolite (SW Pacific) as a case study?" Bulletin de la Société Géologique de France 184, no. 6 (November 1, 2013): 545–56. http://dx.doi.org/10.2113/gssgfbull.184.6.545.
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Abstract The 300 km long allochthonous sheet of oceanic mantle forming the New Caledonia ophiolite displays three specific characters: 1) the ophiolite pile lacks concordant sheeted dykes and pillow basalt layers; 2) the ophiolite, refered to as the Peridotite nappe, is thrusted over the basaltic formations of the Poya terrane which are classicaly thought to originate from a different oceanic environment; 3) The basal contact of the ultramafic sheet is remarkably flat all along New-Caledonia and the Peridotite nappe has not been thickened during obduction, rather it experienced significant extension. This suggests that the peridotites have not been emplaced by a tectonic force applied to the rear. New petrological and geochemical results obtained from mantle rocks finally show that the Poya terrane may originate from the same oceanic basin as the peridotites. In this article, we consider such possible cogenetic links and we propose a simple model for the obduction of the New Caledonia ophiolite in which the Poya basalts represent the original cover of the Peridotite nappe. We infer that continuous uplift of the subducted units buried beneath the oceanic lithosphere in the northern part of New Caledonia drove passive uplift of the ophiolite and led to erosion and to initiation of sliding of the basaltic layer. During the Priabonian (latest Eocene), products of the erosion of the basaltic layer were deposited together with sediments derived from the Norfolk passive oceanic margin. These sediments are involved as tectonic slices into an accretionary wedge formed in response to plate convergence. The volcaniclastic sedimentation ends up with the emplacement of large slided blocks of basalts and rafted mafic units that progressively filled up the basin. Obduction process ended with the gravity sliding of the oceanic mantle sheet, previously scalped from its mafic cover. This process is contemporaneous with the exhumation of the HP-LT units of Pouebo and Diahot. Gravity sliding was facilitated by the occurrence of a continuous serpentine sole resulting from metasomatic hydratation of mantle rocks, which developed during the uplift of the Norfolk basement and overlying Diahot and Pouébo units. Progressive emersion of the obducted lithosphere allowed subsequent weathering under subaerial, tropical conditions.
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León, Francisco José, and Enrico Mora. "Género y vocación científica. Un estudio de caso basado en mecanismos." Revista Internacional de Sociología 68, no. 2 (April 21, 2010): 399–428. http://dx.doi.org/10.3989/ris.2008.06.19.
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Pe-Piper, Georgia, and David JW Piper. "Were Jurassic tholeiitic lavas originally widespread in southeastern Canada?: a test of the broad terrane hypothesis." Canadian Journal of Earth Sciences 36, no. 9 (September 1, 1999): 1509–16. http://dx.doi.org/10.1139/e99-059.
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Two competing models have been proposed for Early Jurassic magmatism on the eastern North American margin. The "broad terrane" hypothesis argues that tholeiitic lavas were extruded over a large area and later eroded. Alternatively, the lavas were extruded only in the basins in which they now outcrop. We compare the stratigraphy and geochemistry of the tholeiitic lavas and dykes from Atlantic Canada with those of the type section of the Newark basin and use this correlation to test these two models. The earliest high-Ti quartz tholeiites in the type section are represented by lavas in the Fundy basin (North Mountain Basalt), Scotian basin, and eastern Grand Banks and by the Shelburne and Ministers Island dykes. Spatial and temporal geochemical variations in the North Mountain Basalt are mirrored by the Shelburne dyke, strengthening the case that the two were geochemically related. Basalts in Grand Manan Island, on the footwall of the Grand Manan fault that bounds the Fundy basin, are geochemically similar to the lowest North Mountain Basalt flow. These observations suggest that the earliest basalt flows were originally more extensive and have become restricted by later uplift and erosion. However, younger magmas in the Newark basin are represented only by the Caraquet, Anticosti, and Avalon dykes in Atlantic Canada, and corresponding lavas were never deposited in the Fundy basin or eastern Grand Banks. Thus, Jurassic tholeiitic lava distribution lies in between the predictions of the "broad terrane" and the "restricted basin" models.
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O’Connell, Katie A., and Richard M. Conran. "Educational Case: Basal Cell Carcinoma." Academic Pathology 8 (January 1, 2021): 237428952199803. http://dx.doi.org/10.1177/2374289521998030.
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The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, see http://journals.sagepub.com/doi/10.1177/2374289517715040 .1
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Persad, A., and V. Mehta. "P.112 Permanent isolated micrographia from traumatic basal ganglia injury." Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques 46, s1 (June 2019): S43. http://dx.doi.org/10.1017/cjn.2019.205.
Full textAbstract:
Background: Micrographia is a rare neurological finding in isolation. Most cases of isolated micrographia have been found in association with focal ischemia of the left basal ganglia. Methods: We present a case of post-traumatic micrographia stemming from contusion to the left basal ganglia. We performed a detailed analysis of the patient’s writing at three-year follow-up. Results: A halthy 15 year old male was admitted following a BM accident. CT showed contusion to the left basall ganglia/external capsule. MRI was negative for underlying lesion. He had a short stay in the ICU and then was discharged. Two years later, he expressed concern regarding difficulty with sma, cramped writing at school. Writing analysis revealed micrographia with spontaneous printing as well as printing to dictation, but not with copied English nor Japanese writing. Conclusions: Isolated micrographia is a rare neurological finding. We present the incidence of this symptom folllowing gliding contusion to the et basal ganglia and external capsule.
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Withers, Robert, Dwight Eggers, Thomas Fox, and Terry Crebs. "A case study of integrated hydrocarbon exploration through basalt." GEOPHYSICS 59, no. 11 (November 1994): 1666–79. http://dx.doi.org/10.1190/1.1443555.
Full textAbstract:
A large unexplored tectonic basin with the potential for significant hydrocarbon accumulations was identified in north‐central Oregon using a variety of geophysical techniques. The basin, informally named after the local town of Heppner, is covered by several thousand feet of Miocene Columbia River Basalt Group (CRBG) but is readily identified by a gravity low against the Blue Mountains Uplift. The Paleocene/Eocene Herren Formation (Pigg, 1961), which outcrops on the Blue Mountains Uplift south of the Heppner Basin, offered good source and reservoir potential. Based on lateral extent, thickness and paleocurrent structures in the Herren Formation, the unit was expected to be present in the basin. Gravity modeling produced nonunique interpretations, thus magnetotelluric (MT) information was used to constrain the CRBG thickness. Static shifts in the MT data were removed using transient electromagnetic (TEM) data before MT data inversion. After extensive experimentation, adequate seismic data were obtained for structural mapping, but the seismic data were interpretable with confidence only after MT determinations of the CRBG thickness. As a result of the favorable geologic and geophysical information, the ARCO Hanna ♯1 well was drilled to 9100 ft (2800 m) near Heppner, Oregon in section 23, T2S, R27E in 1988. The thickness of the CRBG and Oligocene John Day Formation were accurately predicted by the geophysical interpretations. An unanticipated thickness of Eocene Clarno Formation was encountered and drilling ceased in this unit. No Herren Formation was penetrated during drilling. Geophysical well logs indicate the Clarno Formation has densities and resistivities sufficient to account for the gravity and electrical anomalies defining the prospect. Poor seismic quality was explained by the heterogeneous nature of the pre‐CRBG volcanic section encountered in the well.