The dominance, diversity and activity density of rove beetles were studied in Central European apple and pear orchards. Altogether 6 877 individuals, belonging to 271 species and 11 subfamilies were collected. Thirteen species presented a relative abundance from 9 to 2% and amounted to almost 56% of all staphylinids recorded. In dominance order they were: Dinaraea angustula (Gyllenhal), Omalium caesum Gravenhorst, Drusilla canaliculata (F.), Sphenoma abdominale Mannerheim, Palporus nitidulus (F.), Xantholinus linearis (Olivier), Dexiogya corticina (Erichson), Coprochara bipustulata L., Mocyta orbata (Erichson), Oligota pumilio Kiessenwetter, Xanthlinus longiventris (Olivier), Tachyporus hypnorum (F.) and Pycnota vicina (Kraatz). The alpha diversity of staphylinids for different environmental conditions was relatively similar but the Shannon-Weiner Index (H`) was higher than of other similar studies. However, the activity density was higher in pear, in sand and in abandoned plantations; under different environmental conditions this could not be considered uniform in time. After the cumulative studies on the population dynamics, one can conclude that the highest number of species can be found in spring and in summer. Species D. canaliculata and P. nitidulus presented the similar seasonal dynamics in orchards located in different environmental areas, while O. caesum had the same activity density both in apple and pear orchards.
The main objective of this work is to present an innovative method of numerical modeling of anchored piles system acting as a road protection against landslide, called the “2D/3D method”. Firstly, short description of the problem and “state of the art” review are included. An effective methodology of the design supported by the numerical analysis, solving the problem of interaction of a periodic system of piles and the unstable soil mass is presented, for which some detailed information about proposed numerical approach is given. The key idea of 2D/3D method is to join the pile with the 2D plane strain continuum by fictitious connectors of Winkler type with P-Y properties identified during the analysis of a subsidiary 3D problem. Practical example of usage of proposed approach to a real case of a road endangered by a landslide then protected by the piles system is presented. On the base of this example, a discussion about important design issues like internal forces in piles (mainly bending moments) and anchors (tensile forces) or overall stability of the soil-structure system is done.
An effective method for the analysis of soil-structure interaction including the behaviour of cylindrical storage tank with varying wall thickness under the action of constant thermal loading is presented. Elastic half-space and the Winkler model have been used for the description of subsoil. The soil-structure interaction is described by using the power series. A computational example of reinforced concrete tank loaded with constant temperature is given. The analysis of a hydrostatically loaded cylindrical tank performed for the model incorporating elastic half-space shows decrease of radial displacements as well as substantial changes in the distribution of bending moments when compared to the Winkler foundation. Additionally, local increase of subsoil reaction around the slab circumference is observed for the case of elastic half-space, in contrast to the Winkler model. However, in the case of a tank loaded with constant temperature, the solutions for both subsoil models do not differ significantly.
The subject of this paper is an assessment of the accuracy of a solution based on the linear theory of elasticity describing the interaction of a cylindrical reinforced concrete tank with the subsoil. The subsoil was modeled in the form of an elastic half-space and Winkler springs. The behavior of the shell structure of the RC cylindrical tank, and particularly of the ground slab interacting with the subsoil, depends largely on the distribution of the reactions on the foundation surface. An analysis of this structure with the shell fixed in a circular ground slab was carried out taking into consideration the elastic half-space model using the Gorbunov-Posadov approach and, for comparison, the two-parameter Winkler model. Although the results for both subsoil models proved to be divergent, the conclusions that follow the accuracy assessment of a solution based on the theory of elasticity are fairly important for engineering practice.
The subject of this paper is an analysis of the influence of circumferential prestressing on the interaction of cylindrical silos and tanks with the subsoil. The behaviour of the shell structures of RC and PC cylindrical silos or tanks (with circumferential pre-tensioning), and particularly of the ground slab interacting with subsoil, depends largely on the function graphs of the subsoil reactions on the foundation surface. Distributions of the subbase reactions on the ground slab in such structures as silos and tanks have a significant impact on the behaviour of not only the slab itself, but also the interacting shell structure. An analysis of these structures with walls fixed in a circular ground slab and foundation ring was carried out taking into consideration the elastic half-space model using the Gorbunov-Posadov approach and the two-parameter Winkler model. In the computational examples of RC and PC silos and tanks with walls fixed in the circular ground slab or foundation ring, the eventual effects of prestressing obtained as a result of the superposition of internal forces were examined. Although the results for both subsoil models proved to be divergent, the conclusions that follow are fairly important for the engineering practice.
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