Lifetime of plastic pipes can be estimated by integration of a power law describing the crack kinetics. However, this procedure requires an FEM (finite element method) calculation of the possible crack propagation in the pipe to obtain stress intensity factor dependency on the crack length. It is very important for the simulation to consider every possible load that is acting on the pipe. This contribution deals with FEM modelling of a pipe that is loaded by internal pressure, residual stresses and soil loads. Comparison of the factors and pipe lifetime estimation is carried out.
The computational procedure for investigation vibration stability of a flexible rotor consisting of an asymmetric shaft, one disc, and supported by ball bearings is developed in this work. Lagrange equations of the second kind were used for derivation of the motion equation. The vibration response stability of the Jeffcott-like rotor was studied by means of eigenvalues of a transition matrix. Three different methods for approximation of the transition matrix have been investigated. The presented simulations are focused on studying the influence of parametric excitation produced by the shaft asymmetry and self-excitation vibration caused by the shaft material damping. The numerical results proved the applicability of the developed procedure, which has been verified by the direct integration of the motion equation.
The paper presents the results of research work that has been performed on the von Wentzky family’s palace at Rychnów. Firstly, the architecture of the palace is discussed and written sources concerning the village and the von Wentzky family are reviewed. Based on the architectural studies and the analysis of the details, the most important phases of the place’s transformation were defined. The recognition of the wall construction chronology contributed to the identification of two construction and transformation stages. The original Baroque palace, with its modest architecture was erected on a classic three crosswise-section plan by Ernst Fryderyk von Wenzky in 1781. The building had survived without major changes up until the beginning of the twentieth century, when it was transformed in the years 1906–1907. An extension was added to the west elevation as were a loggia and a porch on the avant-corpses. The research work enabled the author to identify the reach of the palace’s Baroque foundations, and it formed the grounds for generating recommendations to conservators concerning repairs and restoration work.
In 2016, on the sesquicentennial anniversary of the death of Peter Joseph Lenné, an exhibition, entitled “Mistrzowskie jak rzadko które…”. Ogrody Petera Josepha Lenné w Polsce, was presented. It constituted the conclusion of a joint Polish and German academic project. As a part of the research project, a comprehensive review of garden and park layouts was performed and the degree to which Lenné himself and his associates had been involved in the design of the gardens was verified. It was also determined whether the projects had been carried out in accordance with the original assumptions of their authors. The projects were assessed on the basis of surviving garden plans and drawings from the collection of the Stiftung Preußische Schlösser und Gärten (SPSG), as well as data obtained during a query of archival materials and field studies carried out in the years 2014–2015.
This paper presents the design and results of mechanism research. A lever mechanism for a gripper was made using monolith technology with constrictions in which the deformations correspond to limited rotation of the links. Unidirectional movement of the drive link is reduced and simultaneously converted into movement of the jaw clamp. Temporary centres of rotation were used to obtain the symmetrical and perpendicular movement of the two ends of the clamp in relation to its axis of symmetry. Computer simulations and tests were performed on a prototype of the gripper mechanism, confirming the adopted predictions of the device’s operation.
The aim of the article includes presentation and interdisciplinary analysis of design solutions proposed in the works awarded in the international urban architecture competition entitled “New life between flyovers” and concerning the area around the cross-city railway line, currently under modernization, running through the Śródmieście district in Kraków, from the area of Miodowa Street to the PKP Kraków Główny station. In the applications, possible scenarios of flyovers space development and the possibilities of integrating the transport route into the historic district have been assessed, taking into account historical urban relations and contemporary technical conditions. The analyses were aimed at optimising future investments so that they can become a starting point for public consultations, drafting a land development plan and determination of the development strategy for the studied area. The applied method may be helpful in determining the directions of a spatial policy aimed at the protection of cultural landscape endangered by overground transport routes.
The small city is a relatively well examined and widely described subject in literature. Usually, the urban structure of the small city is considered in relation to its original and historical spatial layout with juxtaposition of all subsequent developments in relation to the historical core of given settlement. The article attempts to identify various systems of urban structures in which one of the elements is a group or a single multi-family residential building, examine internal and external scenic relations and determine their impact on the landscape of the small city.
The development of particular towns is a factor that determines the economical, social and spatial development of the country. Therefore we turn our attention to it with a critical eye. On 20th October 2015 the government in Poland accepted a bill connected with the Country Town Policy 2023, that is addressed to towns. Its main point is to strengthen towns in their sustainable development, betterment of standards of living and workplace creation. The socio-economical transformation that occurred in Poland in 1989 has caused a lot of changes in the country. In Ukraine it happened in 1991 and it appears that due to various reasons, its transformation seems to be a much longer process and the process has not finished yet. This article focuses on the development of small towns in Ukraine and Poland, which, in currently difficult times, find themselves in a hard and unstable socio-economic situation. This article analyzes the economic, demographic and spatial aspects of small towns in Ukraine and Poland.
This paper provides an overview of wind observations in Romania with historical data, particularly after the establishment of the national meteorological network in 1884. Data on wind directions and velocities is presented, focusing on a sample of fourteen cities including the capital Bucharest. The historical evolution of national zonation maps for wind pressure is shown. A statistical description of the maximum annual wind velocity data is also presented.
Terrain surface subsidence observed in mining areas results in the flattening of riverbeds and their embankments. This leads to increasingly deep erosion and siltation of riverbeds and surface currents, which causes the emergence of permanent overflow lands. This paper presents hydro – engineering solutions applied in the areas of the mining activity of JSW S.A., which serve the purpose of repairing and eliminating mining damage in the existing infrastructure. The presented repair measures make it possible to eliminate the threat of flooding in mining areas.