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Calculation of combined steel-concrete structures shall be conducted in stages. Before monolithic slab concrete gains strength, metal structure is the only structure part that carries loading of its own weight. However, after concrete gains strength, the whole calculated loading is carried by whole reinforced monolithic concrete slab where axis position changes. The article describes main principles of the technique of imaginary hinges installation for the forces calculation in static indefinite continuous structures under conditions of mathematical axis position change in stiffening girder. That enables to simulate the stress-deformation state in the combined structures elements at the initial design stage. This technique is used for the calculation and results analysis for combined structure with composite reinforced concrete top band and steel suspension taking into account of their work stages.
Retaining walls with the use of reinforced soil technology are frequently used in building light retaining constructions, whose facing is made from gabion baskets. Geosynthetics or steel double woven mesh play the role of reinforcement rod in this type of structures. A good alternative for steel woven mesh is welded mesh, which is not prone to the change of mesh geometry during stretching in the main direction. The objective of this dissertation is to find an answer to the question of the steel welded mesh applicability as ground reinforcement in light gabion retaining structures, as well as the comparison of deformations of both meshes types in different ground conditions. The work contains the numerical analysis of meshes stretching, including their assembling in soil using different vulnerability coefficient value. The article has been summarized with conclusions, plans for further experimental research as well as a comparison with previous numerical analyzes.
This work consisted in studying the frequency of deformations of the attachment organ in specimens representing the family Diplozoidae, occurring in roach, common bream, and white bream from live different water bodies. These water bodies differed in morphometric parameters, levels of eutrophication, and character of their pollution. The presence of three types of deformation was stated. The most common were deformations of type II (morphological changes of clamps, such as sclerite deformation, incomplete sclerite separation or sclerites missing altogether in a clamp), while less frequent were those of types I (chaoges in the size of clamps not associated with the structural changes) and III (missing clamps in a set). Most frequently anomalies of the attachment organ were stated in polluted Łyna River, polluted Wulpińskie Lake, and in dystrophic Warniak Lake. Less frequent were anomalies in less eutrophied lakes Dgał Wielki and Ukiel. Also the prevalence values of those parasites were the highest in the polluted water bodies. The present study suppons believes of other authors, that both infection parameters of Diplozoidae affecting fishes and deformations of monogeneans' attachment apparatus can be treated as indicators of environmental pollution.
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The energy of sheet bending on a crank-type press

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The analytical method of power calculation of crank-type press working stroke is developed instead of graph analytical method. This analytical method allows substantially reducing working hours of calculation and promoting exactness of the results. Bending and coining are offered to execute separately. That will allow to make this processes more economically and to reduce depreciate charge.
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Dynamics of wear of the cutting elements of tillers

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The paper discusses theoretical studies of wear of the cutting elements of working bodies of tillers to develop their technological process of hardening, providing on the one hand increase their longevity, and with another - providing quality tillage. It shows the dependence of the wear rate on the length of the cutting edge cultivator paws. The interaction of the blade working organs of tillers of the soil with the environment was characterized. The diagram of the forces acting on the blade body and working movement direction in the soil was given. The analysis presents dependence between the linear wear lancet cultivators paw thickness and such factors as the way of friction, normal specific dynamic pressure of the soil, the hardness of the material clutches, friction area. The paper shows the effect of the angle between the polar axis and the radius of curvature of the cutting edge of the blade cultivator paws on the value of its wear. The regularities of changes in the intensity of wear feet are observed along the length of its cutting edge.
This paper presents the results of the triaxial tests performed on medium sand and sandy clay samples. The shear strength and deformation characteristics from consolidated drained (CD) tests performed in a controlled saturation state were determined. The study was conducted in a modern apparatus for triaxial testing of unsaturated samples. Test specimens with a diameter of 70 mm and height of 140 mm were prepared by compaction in a laboratory in a special form. The main aim of this study was to investigate the effect of matric suction on the shear strength and deformation characteristic of medium sand and sandy clay. The axis translation technique was used to apply matric suction to soil specimens.
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A huge development of technical infrastructure, including the construction of many high-rise buildings, roads, railroads and extension of subway lines, took place over the recent years in Poland. Therefore, numerous planned investment projects require geotechnical data documenting the variation of soil parameters found in the subsoil. The shear wave velocity is one of the most important input parameters to represent the stiffness of the soil deposits. This paper focuses on the methods and devices using measurements of the shear wave velocity to estimate the initial shear modulus in cohesive soil. It is preferable to measure VS by in situ wave propagation tests, however it is often economically not feasible in all regions of Poland. Hence, a reliable correlation between shear wave velocity and parameters measured in triaxial cell or static penetration parameters would be a considerable advantage. This study shows results obtained from the bender elements tests and fi eld techniques – seismic cone penetration test and seismic flat dilatometer, performed on overconsolidated cohesive soils in Warsaw. On the basis of the test results possible correlations between shear wave velocity (initial shear modulus), mean effective stress and void ratio are considered and four original empirical relationships are proposed. Moreover, the proposed formulas by two different techniques using triaxial apparatus and also RCPT cone were examined. The proposed formulas show a reasonable agreement with direct shear wave velocity profiles for clays and might be incorporated into routine laboratory and field practice.
The study was done on common carp larvae, the embryonic development of which took place in clean tap water (control – K group) or at 0.2 mgˇdm3 of copper (Cu group). The experiments were carried out until the 20 day from hatching. Among newly hatched larvae four types of body malformations were distinguished: A – curvature of the spine, B – C-shaped larva, E – deformed yolk sac, G – shortened body. These deformations are not copper-specific, and were observed also in fish exposed to other heavy metals. Deformations that impair larval locomotion must adversely affect feeding efficiency, thus would reduce larval survival. That was confirmed by the results concerning survival of larvae fed Artemia sp. nauplii. Only the larvae able to take up exogenous food survived until the end of the experiment. Copper exposure affected survival of larvae. Starved normal larvae from control group survived 19 days and started to die from the 13th day.
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Elasticity characteristics of fruit

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