21 research outputs found
Development and Characterization of Lightweight Geopolymer Composite Reinforced with Hybrid Carbon and Steel Fibers.
The aim of this paper is to analyze the influence of hybrid fiber reinforcement on the properties of a lightweight fly ash-based geopolymer. The matrix includes the ratio of fly ash and microspheres at 1:1. Carbon and steel fibers have been chosen due to their high mechanical properties as reinforcement. Short steel fibers (SFs) and/or carbon fibers (CFs) were used as reinforcement in the following proportions: 2.0% wt. CFs, 1.5% wt. CFs and 0.5% wt. SFs, 1.0% wt. CFs and 1.0% wt. SFs, 0.5% wt. CFs and 1.5% wt. SFs and 2.0% wt. SFs. Hybrid reinforcement of geopolymer composites was used to obtain optimal strength properties, i.e., compressive strength due to steel fiber and bending strength due to carbon fibers. Additionally, reference samples consisting of the geopolymer matrix material itself. After the production of geopolymer composites, their density was examined, and the structure (using scanning electron microscopy) and mechanical properties (i.e., bending and compressive strength) in relation to the type and amount of reinforcement. In addition, to determine the thermal insulation properties of the geopolymer matrix, its thermal conductivity coefficient was determined. The results show that the addition of fiber improved compressive and bending strength. The best compressive strength is obtained for a steel fiber-reinforced composite (2.0% wt.). The best bending strength is obtained for the hybrid reinforced composite: 1.5% wt. CFs and 0.5% wt. SFs. The geopolymer composite is characterized by low thermal conductivity (0.18-0.22 W/m ∙ K) at low density (0.89-0.93 g/cm3)
Mechanical properties of geopolymer concretes reinforced with waste steel fibers
The article presents the research that try to determinate the possibilities of utilization the waste came from used tires to create the composites based on geopolymer matrix. The tire is multicomponent construction. It mainly consists of elastomer (rubber), metal and textile fibres such called textile cord. A lot of components causes difficulties in the tire recycling process. The main aim of the research was determinate the possibilities of recycling the waste steel from used tires in geopolymer composites and develop the eco-friendly material for construction industry. The matrix based on fly ash from power station located in city named Skawina (Poland) and fine sand at a ratio of 1:1. The process of activation was made by 10M sodium hydroxide solution combined with the sodium silicate solution. In order to manufacture these composites the addition of 2% and 3.5% of waste steel fibres by mass was applied. Also specimen without steel fiber reinforcement were made to get reference specimens. The waste steel fibres came from recycling company from Argentina - 'Regomax'. The specimens were prepared according to the methodology described in the standard EN 12390-1. The research methods used were: microstructure research, tensile strength and compressive strength tests as well as analysis of breakthroughs.Fil: Gailitis, R. Riga Technical University; LetoniaFil: Korniejenko, K. Cracow University Of Technology; PoloniaFil: Lach, M. Riga Technical University; LetoniaFil: Sliseris, J. Riga Technical University; LetoniaFil: Moran, Juan Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Rodriguez, Exequiel Santos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Mikula, J. Cracow University Of Technology; Poloni
Tensile creep of cement and concrete composites: Monitoring by means of 2D-digital image correlation
Creep and shrinkage of Cement and Concrete Composites (CCC) are significant properties that need to be considered to use these materials in practice. Many previous scientific studies re-vealed CCC creep characteristics under sustained compression and shrinkage, using traditional test methods from design standards. Because of the complexity of experimental procedures, CCC creep in tension has not been studied as close. Furthermore, there is no unified standard that proposes applicable testing methods or specific testing apparatus. This study examines the suitability of 2D— Digital Image Correlation (DIC) to observe the creep deformations of specimens under tension. Or-dinary Portland cement (OPC) mortar with 1% polyvinyl alcohol (PVA) fibres has been investigated in the research. Compact tension (CT) specimens 150 × 150 × 12 mm (with a notch) were used. Creep deformations under sustained uniaxial tension (applied loading corresponding to 60% of the ultimate strength) were measured. DIC images were captured using an entry/mid-level DSLR camera. Results show that DIC is suitable for studying uniaxial tensile creep of cement and concrete com-posites. Deformation of specimens in tension was similar to that measured using the conventional method (using surface-attached gauges)
Supporting technical post-graduate studies with some remote-access tools according to the project ‘PIT Mobilne studia podyplomowe we współpracy z przemysłem’ (PIT Mobile postgraduate studies in collaboration with industry)
Celem artykułu jest analiza możliwości wdrożenia różnych form wsparcia procesu nauczania przez narzędzia zdalne na przykładzie projektu „PIT Mobilne studia podyplomowe we współpracy z przemysłem” finansowanego z Europejskiego Funduszu Społecznego. Obejmuje on dwa kierunki technicznych studiów podyplomowych realizowane w formie blended learning na Wydziale Mechanicznym Politechniki Krakowskiej w latach 2013-15. W artykule przedstawiono nowoczesne możliwości rozwoju studiów podyplomowych o profilu technicznym dopasowanych zarówno do potrzeb studentów, jak i współczesnego rynku pracy. Zastosowane metody badawcze to: analiza krytyczna źródeł literaturowych, case study oraz analiza badań ankietowych przeprowadzonych na uczestnikach studiów podyplomowych w ramach ewaluacji projektu.The aim of the article is to analyze the possibility of implementation of various forms of learning support such as remote access tools on the example of the project ‘PIT Mobilne studia podyplomowe we współpracy z przemysłem’ (PIT Mobile postgraduate studies in collaboration with industry), financed by the European Social Fund. The project includes two technical postgraduate programs realized in the form of blended learning at the Cracow University of Technology Faculty of Mechanical Engineering in the years 2013-15. The article presents a modern opportunities postgraduate studies tailored to the needs of students and the contemporary labor market. The research methods used are: a critical analysis of literature sources, case studies and analysis of the survey conducted on the participants of postgraduate studies in the context of project evaluation
Possibility of use of m-learning support for postgraduate courses in welding
Celem artykułu jest pokazanie możliwości wsparcia nowoczesnymi narzędziami e-nauczania i m-nauczania kształcenia na studiach podyplomowych w zakresie spawalnictwa. Artykuł przedstawia możliwości wykorzystania różnych form e-nauczania i omawia możliwości wsparcia nauczaniu zagadnień z zakresu spawalnictwa przez innowacyjne narzędzia tj. aplikacje mobilne. Artykuł bazuje na case study projektu „PIT Mobilne studia podyplomowe we współpracy z przemysłem” finansowanego z Europejskiego Funduszu Społecznego i realizowanego na Wydziale Mechanicznym Politechniki Krakowskiej w latach 2013-15, a także późniejszym wykorzystaniu narzędzi do kontynuacji studiów podyplomowych w kolejnych latach. Zastosowane metody badawcze to: analiza krytyczna źródeł literaturowych oraz case study wsparcia e-learninigiem i m-learningiem studiów podyplomowych z zakresu spawalnictwa.The main aim of the article is to present the possibilities of support postgraduate studies in the field of welding of modern tools for e-learning and m-learning. The article presents the new ways of support for various forms of innovative forms of learning and discusses the application on mobile devices in the area of teaching of welding technologies. The article is based on a case study of the project ‘PIT Mobilne studia podyplomowe we współpracy z przemysłem’ (’PIT Mobile postgraduate studies in collaboration with industry’), financed by the European Social Fund. It was implemented at the Faculty of Mechanical Engineering of the Cracow in the years 2013-15, and the use of the tools to continue postgraduate studies in subsequent years. The research methods used are: critical analysis of literature sources and the case study of support post-graduate studies in the field of welding by of e-learning and m-learning tools
Possibility of use of multi-criteria decision analysis for desing e-learning courses
Celem artykułu jest analiza krytyczna możliwości wykorzystania metod wielokryterialnych w projektowaniu szkoleń e-learningowych. Metody wielokryterialne, stosowane do wsparcia procesu decyzyjnego, są odpowiedzią na złożoność współczesnych problemów rozwiązywanych w warunkach niepewności, niepełnych danych oraz zmieniającego się otoczenia. Artykuł prezentuje analizę literatury w aspekcie wykorzystania metod wielokryterialnych we wsparciu e-learningu oraz koncepcję wykorzystania metody Analitycznego Procesu Hierarchicznego (AHP) w projektowaniu kursu e-learningowego.The aim of the article is to analyze the possibility of using multi-criteria methods for support in the designing e-learning curses. Multi-criteria methods used to support the decision-making process, are a response to the complexity of contemporary issues that in conditions of uncertainty, incomplete data and changing environment. The research methods used in the article are: critical analysis of literature sources and the example of the use of the Analytic Hierarchy Process (AHP) in the design of e-learning course
The possibility of using virtual reality as innovative tools for supporting engineers education
W ostatnich latach wirtualna i rozszerzona rzeczywistość znajduje coraz szersze zastosowanie w różnych dziedzinach ludzkiej działalności, w tym w edukacji. Celem artykułu jest analiza możliwości wykorzystania innowacyjnych narzędzi, opartych na rzeczywistości wirtualnej i rozszerzonej, w procesie kształcenia w szkołach wyższych na kierunkach technicznych. Artykuł przedstawia obecne zastosowania rzeczywistości wirtualnej i rozszerzonej w edukacji inżynierów różnych specjalności w oparciu o studia przypadków. W artykule przedstawiono korzyści i potencjalne zagrożenia związane z korzystaniem z tego rodzaju wsparcia dydaktycznego. Główne zastosowane metody badawcze to krytyczna analiza literatury przedmiotu poparta studiami przypadku, w tym opis studium przypadku zastosowania rzeczywistości rozszerzonej w kształceniu w zakresie budownictwa analizowanego w ramach wizyty studyjnej na uniwersytecie Pontificia Universidad Católica del Perú.The main motivation for research work is development of new based on virtual and augmented reality. This tools become more and more popular in different area of human activities, including education. Some of them is also applicable for engineering curricula. The aim of the article is to analyse the possibility of using innovative tools such as virtual and augmented reality for support in higher education. It presents different way of application virtual and augmented reality in higher education based on case studies form engineering, exemplary possibilities of education further material engineers, civil engineers, mechanical engineers and other specialists. The article presents benefits and potential threats for using this kind of tools. The research methods used in this article are a critical analysis of literary sources supported by case studies from literature and case study from collaborating university - Department of Engineering, Civil Engineering Division, Pontificia Universidad Católica del Perú. The university developed the system based on augmented reality that is using for visualisation cultural heritage objects. The system is used for education as well as research purposes