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1
EN
The modern management the maintenance the state of fitness and the explorational service of machines this about many more than the traditional making the repairs and the preservation of equipment. The ability of survival of whole organization depends from effective strategies the maintenance of fitness often and the technical service of machines the financial shape of enterprise from which depends often. Method TPM becomes with modern tool of maintenance in many enterprises the fitness of machines.
2
EN
Building construction organizational structures is aimed at creating appropriate conditions for the cooperation of construction staff in order to complete a specific construction object. It should be associated with the process of organizing and allocating work, decision-making rights and resources to individual construction participants, along with providing appropriate resources so that they can perform their tasks correctly and safely. Construction organizational charts are helpful. The article presents an example procedure for designing an organizational structure that may be useful in construction management.
EN
The restrictions on carbon dioxide emissions introduced by the European Union encourage experimental work on new-generation materials containing smaller amounts of clinker. At present, silica fly ashes from the combustion of hard coal are widely used in the technology of cement and concrete in Europe and Poland. This research aims to assess the physical and chemical properties of fly ashes from the thermal treatment of sewage sludge for use in concrete technology in relation to applicable standards and determine their impact on the natural environment. The established concentrations of heavy metals are below the maximum values required when discharging sewage into the ground or waters and also meet the necessary leaching limits when inert waste is allowed to be landfilled and on substances particularly harmful to the aquatic environment. On this basis, it was found that the migration of heavy metals from concrete with the addition of ashes to the water environment is insignificant and should not be a major problem. In addition, the tests showed that the activity index did not exceed the limit value.
EN
Caring for the environment, in accordance with the principles of sustainable development, as well as the increase in the standard of living of society, introduces the need to conduct proper waste management. Construction is an industry with great potential for the management of glass waste as part of material recycling. The construction sector is characterized by high material consumption, with a limited amount of natural resources, meaning that research is constantly being performed on the possibility of replacing them with other common ingredients. A feature of the building materials industry is also the pursuit of continuous improvement of the properties of manufactured materials. The paper presents the research results on the impact of the partial replacement of Portland cement and aggregate with glass waste on strength parameters and frost resistance. For the purpose of experimental work, a concrete mix based on the C20/25 standard concrete with CEM I 42.5R Portland cement, in which from 0 to 20% of the cement or aggregate weight is replaced with glass waste (i.e., glass flour and glass cullet), is designed. In the test range, the glass flour slightly affected the deterioration of the compressive strength, while the glass cullet had no effect on the compressive strength after 56 days of maturation. Moreover, the addition of glass flour increases the bending strength, while the addition of glass cullet maintains a comparable bending strength compared to the reference concrete. The obtained concretes are frost-resistant concrete F150.
5
Content available remote Modelling in the identification of threats to the functioning of technical system
EN
Modern technical systems used in practice (machines, vehicles, military technology) are subject to automatic degradation of the technical condition, which forces modelling to identify changes in this state. The available modelling methods in identifying changes in the technical condition of such systems make it possible to supervise the developing threats to the correctness of their functioning. The aim of the work was to present available methods and tools for modeling and identifying evolving threats to complex technical systems in terms of description and indication of the premises for their use. Modern technical systems (machines and military technology) are characterized by such features as: functionality, reliability, readiness, security, mobility, and operational vulnerability. Identification of threats to the functioning of technical systems through modeling therefore concerns the construction of models of the test object, the reconstruction of the state of the object and its prediction. The existing methods of identification can be divided into methods of identifying static and dynamic properties. The current availability of computers and simulation studies of the dynamics of objects allows attempts to identify the dynamic properties of objects throughout its life cycle, using various models. The considerations presented in this paper concern a modern approach to modeling the dynamic state of objects. The evolutionary dynamic models created in this way should improve the methodology and reasoning in the assessment of the dynamic state, often used for optimization and supporting operational decisions, which is the research niche of this article.
PL
Nowoczesne systemy techniczne stosowane w praktyce (maszyny, pojazdy, technika wojskowa) podlegają automatycznie degradacji stanu technicznego, co wymusza potrzebę modelowania oraz identyfikację zmian tego stanu. Dostępne metody modelowania identyfikacji zmian stanu technicznego takich systemów pozwalają na nadzorowanie powstających zagrożeń dla prawidłowości ich funkcjonowania. Celem pracy było przedstawienie dostępnych metod i narzędzi do modelowania i identyfikacji ewoluujących zagrożeń dla złożonych systemów technicznych w zakresie opisu i wskazań przesłanek do ich wykorzystania. Współczesne systemy techniczne (maszyny i technika wojskowa) charakteryzują się takimi cechami jak: funkcjonalność, niezawodność, gotowość, bezpieczeństwo, mobilność, podatność operacyjna. Identyfikacja zagrożeń dla funkcjonowania systemów technicznych poprzez modelowanie dotyczy więc budowy modeli badanego obiektu, rekonstrukcji stanu obiektu i jego predykcji. Istniejące metody identyfikacji można podzielić na metody identyfikacji właściwości statycznych i dynamicznych. Obecna dostępność komputerów i badań symulacyjnych dynamiki obiektów pozwala na podejmowanie prób identyfikacji właściwości dynamicznych obiektów w całym cyklu ich życia, przy użyciu różnych modeli. Przedstawione w artykule rozważania dotyczą nowoczesnego podejścia do modelowania stanu dynamicznego obiektów. Stworzone w ten sposób dynamiczne modele ewolucyjne powinny usprawnić metodologię i rozumowanie w ocenie stanu dynamicznego, często wykorzystywanych do optymalizacji i wspomagania decyzji operacyjnych, co stanowi niszę badawczą.
EN
Concrete is currently the most widely used man-made composite material and second only to water in the entire range of materials used. It is a material with a high potential to adapt to specific operating conditions and can be made from local raw materials (aggregate, cement, water, and mineral additives), which can be selected to minimize the carbon footprint. The use of fly ash from the thermal conversion of sewage sludge in concrete is in accord with the advice on waste management proposed in the European Union. This paper presents the results of research on the effect of the partial replacement of Portland cement with this material on the strength parameters, frost resistance, and carbonation of concrete compared to reference concrete and to concrete containing a conventional additive – siliceous fly ash. In addition, the potential environmental impact of the use of sewage sludge ash was investigated by determining the leachability of heavy metals. Concrete mixtures of C20/25 ordinary concrete, based on CEM I 42.5R Portland cement, with varying ash contents comprising 0–20% of the cement mass, were produced for the experimental work. The obtained test results confirmed the possibility of producing plain concrete modified with fly ash from the thermal treatment of sewage sludge and the concrete’s compliance with the environmental requirements relating to the leaching of heavy metals.
PL
Konstrukcje budowlane i ich elementy muszą spełniać wymagania dotyczące stateczności, sztywności i nośności. Są to warunki decydujące o bezpieczeństwie konstrukcji zarówno w okresie budowy, jak i eksploatacji. Ocena bezpieczeństwa odbywa się na podstawie badań diagnostycznych mających na celu kontrolę jakości wykonania wznoszonych obiektów lub zlokalizowanie uszkodzeń elementów konstrukcji powstałych podczas eksploatacji. W artykule skupiono się na eksperymentalnej analizie modalnej SISO ceramicznych elementów murowych. Doświadczenie przeprowadzono na dwudziestu próbkach cegły pełnej, z czego celowo uszkodzono połowę z nich, aby możliwa była ocena przydatności zastosowanej metody w postawionym problemie badawczym.
EN
Building structures and their elements must meet the requirements related to stability, stiffness and strength. These are the conditions that determine the safety of the structure both during construction and operation. The safety assessment is carried out on the basis of diagnostic tests aimed at checking the quality of the erected objects or locating damages to structural elements caused during operation. The work focuses on the experimental SISO modal analysis of ceramic masonry elements. The experiment was carried out on twenty samples of solid and perforated bricks, half of which were deliberately damaged and thus to be able to assess the suitability of the method used in the research problem posed.
PL
Współczesne konstrukcje kratownicowe są projektowane, aby sprostały wymogom wytrzymałościowym niezagrażającym bezpieczeństwu ich użytkowania. Może to spowodować fakt, że wpływ drgań na konstrukcję kratownicową narażoną na działanie sił poziomych, jak też sił poprzecznych spowodowanych działaniem wiatru może być niebezpieczny dla bezpiecznego użytkowania (np.: konstrukcje mostowe). Uznając potrzebę doskonalenia oceny ich stanu, jak również współczynników bezpieczeństwa, wykonano badania destrukcji zamodelowanego elementu przęsła mostowego za pomocą metody teoretycznej analizy modalnej.
EN
Contemporary truss structures must maintain appropriate strength requirements for safe use. This may result in the fact that the influence of vibrations on a truss structure exposed to horizontal forces as well as transverse forces caused by wind may be dangerous for safe use (e.g. bridge structures). Recognizing the need to improve methods of testing truss elements for the purpose of assessing their condition as well as assessing the safety factors in this work, an attempt was made to examine the destruction of the modelled bridge span element using the theoretical modal analysis method.
PL
W artykule poddano weryfikacji proponowaną w metodykę drganiowego badania degradacji konstrukcji budowlanych w zastosowaniu do oceny miar rozpływu energii drganiowej w segmentach murowych (ceglanych). Analizy teoretyczne i weryfikacja praktyczna badania wrażliwości informacyjnej proponowanych miar procesów drganiowych wskazują na szerokie możliwości ich zastosowań, w szczególności możliwe jest zastosowanie przedstawionej metodyki w zarządzaniu kontrolą jakości.
EN
The presented study subjected to the verification of dictated vibration methodology study of building structures degradation in the application to the assessment of vibration energy flow measurements in masonry (brick) segments. Theoretical analysis and practical verification of the information sensitivity testing of proposed measures of vibration processes indicate the wide possibilities of their applications, it is possible to apply the presented methodology in the quality control management.
EN
Steel structures are subject to large dynamic loads clearly reflected by generated vibration processes. The vibrations may affect state of serviceability of structures by lowering comfort of persons working there as well as possible reaching the level hazardous to safety of the structures. The effect of vibrations to structure is mainly manifested by additional stresses in a given cross-section, which are summed up with those resulting from static loads. The dynamic loads may cause damaging effects in buildings of various structural types or even lead to their destruction. Judging the necessity of improving the quality assessment methods of building structures for purposes of estimation of their state as well as safety factors for lattice structures, the author of this work undertook an attempt to investigate destruction process of selected object by using the modal analysis method.
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