Impact of seismic-type shock parameters on the soil-structure interaction effect in the USC mining region

The paper deals with seismic-type surface and building vibrations randomly occurring as a result of rockbursts in mining regions (random events as with earthquakes). The focus is on the problem of ground vibrations transmission to building foundation – it is one of very important phenomenon associated with soil-structure interaction effect. One of the ways of estimation of possible differences between simultaneously developing free-field vibrations next to a building and building foundation vibrations, i.e. using a ratio of response spectra (RRS), is applied to this study. Analysis concerns the ratio of dimensionless and dimensional acceleration response spectra (β and Sa) – denoted as RRS(β) and RRS(Sa), respectively. Horizontal vibrations parallel to the transverse (x) and longitudinal (y) axis of the representative (typical) two-storey, masonry office building are discussed. Calculations are based on the results of in situ surface vibration measurements performed in the seismically active Upper Silesian Coalfield (USC) mining area in Poland (long-term, full-scale monitoring). Evaluation of the dependence of the curves of ratio of response spectra on some parameters corresponding to mine-induced vibrations (i.e. epicentral distance, mining shock energy, peak value of free-field vibrations) is executed. From the obtained results, it can be definitely concluded that the influence of the most important mining tremor parameters (i.e. epicentral distance, mining shock energy, peak value of free-field vibrations) on the ratio of response spectra calculated in the successive ranges of these parameters, is clearly observed

Vibration induced by railway traffic-zones of influence on buildings and humans

The article presents selected results of evaluation of the harmfulness of buildings vibrations and influence on humans in buildings caused by railway traffic. The results presented in the paper were part of larger group of in field test which gather, were the basis of creation the zones of influence of railway vibrations. The paper presents the methodology of field test as well as some selected results. The discussion of the results leads to conclusions which are presented, as mentioned above, zones of influence of railway vibrations on building construction as well as on human in the buildings. The proposed zones are different for cargo and passenger trains. The ranges of zones are also different in case of building structure and human perception. All analyzes are compatible with polish codes PN-B-02170:2016 [1] and PN-B-02171:2017 [2] and executed by accredited laboratory with significant participation of the authors. The proposed zones were assumed by manager of the national railway network PKP PLK S.A

Numerical 2D Simulation of Morphological Phenomena of a Block Ramp in Poniczanka stream: Polish Carpathians

Description of flow in streams is a very complex problem. Physical analyses of this phenomenon provide a quantitative description of water flow, allowing creating mathematical models having practical meaning. Fast development of programs has improved their practical implementations, so the results of analyses and solutions of flow problems in both open channels and pipes, obtained through numerical modelling, can be applied in practical solutions. Numerical models are often very useful in studies covering a wide range of analyzed parameters. However one must understand that the similarity between a real river and its model could only be partially verified. The main purpose of this paper is to investigate the effect of the selected boulder block ramp hydraulic structure on Poniczanka stream on sediment transport, using the numerical model CCHE2D, assuming several situations, depending on the type of the river bed (erodible, non-erodible, rocky) and kind of rock blocks used for hydraulic structure construction. The obtained results were compared with the Hjulström graph, which is a classic approach for the identification of fluvial processes in the river channel (erosion, sedimentation, transport). In addition to these two methods, field observations were carried out which included the determination of changes in the horizontal and vertical changes of the riverbed morphology of the examined section river reach. The obtained results allowed determining the compatibility of these three methods for evaluation of sediment transport rate of river bed material in the analyzed sections of Poniczanka stream which are engineered with boulder block ramp hydraulic structures (BBR)

A multi-criteria approach for selecting the utility function of the historical building "Stara Polana" located in Zakopane

In this article, the authors present a proposal for a hybrid decision model in order to select a utility function for a historic building, taking into consideration the criteria of the Małopolska Certificate of Energy Efficient Building as well as additional criteria for the comfort of the users. The description of the criteria and the proposed decision-making model focus on the Stara Polana historical building, which is located in Zakopane

Identification of signal characteristics in the analysis of free-field vibration caused by trains

The paper deals with a selection of free-field vibration measurement results. The study is based on the vibration measurements. Vibration acceleration records and their dependence on the position of the accelerometer are shown. The study presents the results obtained in time domain and frequency domain (FFT). Nevertheless, the main aim of the paper is to compare the results of analysis which use the time – frequency domain. A Short-Term Fourier Transform (STFT) and Continuous Wavelet Transform (CWT) are used. The use of new methods to assess the dynamic characteristics is to validate the usefulness of proposed technique for non-stationary signals

Vibrations of free-field and building caused by passages of the Pendolino train

The objective of the paper was to conduct dynamic measurements of free-field vibrations in three profiles and establish decay relations of propagating vibrations. The sources of vibrations were passages of the Pendolino train with dedicated speeds from 40 to 293 km/h. In each profile, soil properties tests were carried out. Based on the data for a few selected speeds of the Pendolino train’s passages, the Vibration Reduction Coefficients (VRC) were determined at selected points. The paper is also focused on the analysis of vibrations of the selected one-storey masonry residential building located in the vicinity of one of the profiles and their evaluation of the harmfulness on the building structure using standard scales of dynamic influence

Dynamic investigations of various civil engineering structures due to ambient and mining tremors

The first part of the study deals with evaluation of dynamic characteristics of selected typical industrial facilities, such as the extraction steel tower, reinforced concrete tower skips. These structures are located in the coal mine area. The constructions of the test items are varied and complicated, which causes difficulties in the research in situ. In the investigation we used normal and emergency operation of lifting equipment, the effect of wind gusts and rhythmic man swaying. The second part of the study involves the determination of the dynamic characteristics of tailing dam. In this case mining tremors were used as the sources of vibration excitations. By using natural vibration excitation source it was possible to determine the lowest frequency of free vibration of the tailing dam. The third part of the paper focuses on the results of measurements of mine-induced ground vibrations and vibrations of residential buildings of various types. Typical one-family masonry houses as well as 5 and 12 storey reinforced prefabricated buildings were examined. The studies were conducted to determine the transmission of free-field vibrations to the building foundations. According to the significant differences between the simultaneously measured ground and building foundation vibrations, results of experimental tests obtained by means of response spectra are essential for the proper adoption of kinematic loads for dynamic models of these structures. The results of experimental studies were the basis for the verification of dynamic models of investigated structures

Impact of the vibrations on the environment caused by passages of trains at variable speed

The paper deals with negative environmental impact caused by the passages of different kinds of trains at variable speed. The study is based on the measurement results which took place in Poland in 2013 on the railway line no. 4. The effect of the traction unit – Pendolino (EMU 250) on the vibration climate was analysed. The impact of passages of new trains was compared to currently operated rolling stock. The speed of trains was varying between 40 and 250 km/h. Vibration measurements were conducted by stuff of an accredited Laboratory of Structural Mechanics at Cracow University of Technology (Accreditation No. AB 826). The influence of the indicated vibrations due to passages of the trains on the building in the neighbourhood of the line was investigated. The vibration assessment was done for horizontal components of vibrations according to Polish standard code. Assessment of environmental impact was presented by indicator of perceptibility of vibration through construction (WODB), which refers to the Scales of Dynamic Influences (SDI scales). The limits specified by standards in any of the passages have not been exceeded. The change of speed or rolling stock resulted in a change in the characteristic of the vibration spectrum

Analiza nieliniowa wieży wyciągowej na obciążenia sejsmiczne

In recent years, the intensity of the loads caused by mining activity has increased in Poland. This exploitation is often carried out in urbanized areas, so their operation on structures is not only a social problem, but also a challenge for engineers. Many of the surface facilities safe use affects the failure-free operation of the mine. The paper presents the results of representative measurements of surface vibrations from mining areas in Poland and earthquakes and their comparison. Particular attention was paid to the values of PGA/PGV ratios and the most commonly used methods for dynamic calculation of the structure. The last part of the work presents an experimentally verified dynamical model of the selected RC skip tower. The forced vibrations of the model were analysed by taking representative earthquakes and mining origin tremors. Time history non-linear analysis and push over methods were used. The nonlinear concrete model was adopted in the analyses. The results show that pushover analysis is not able to capture the seismic demands imposed by far-field or near-fault ground motions, especially for short-period systems for which it can lead to significant errors in the estimation of the seismic demands. The results confirmed the qualitative results of the linear analysis. The carried out inventory of cracks to the skip tower also allowed their location in bearing elements of the skip tower. The results of non-linear numerical analyses allowed us to assess the safety of the structure.Dodatkowym obciążeniem działającym na konstrukcje budowlane są drgania przenoszone przez grunt. Z reguły takie konstrukcje, gdy znajdują się poza obszarami trzęsienia ziemi, nie są przystosowane do takich dodatkowych obciążeń. Na terenach dotkniętych wstrząsami górniczymi konstrukcje nie były projektowane na takie obciążenia. W projekcie uwzględniono tylko obciążenia stałe i ciężar własny, obciążenia technologiczne oraz obciążenia od podmuchów wiatru. W ostatnich latach w Polsce wzrosła intensywność obciążeń powodowanych działalnością górniczą. Eksploatacja ta często prowadzona jest na terenach zurbanizowanych, dlatego ich eksploatacja i wpływ na budynki staje się nie tylko problemem społecznym, ale także wyzwaniem dla inżynierów. Ich zadaniem jest zapewnienie bezpieczeństwa konstrukcji i osób przebywających w tych budynkach. Wiele obiektów naziemnych znajduje się bezpośrednio na terenach kopalni. Ich bezpieczne użytkowanie wpływa na bezawaryjna prace kopalni. Awarie obiektów powierzchniowej infrastruktury budowlanej kopalni prowadzą do dużych strat finansowych i powodują problemy społeczne. W pracy przedstawiono wyniki reprezentatywnych pomiarów drgań powierzchniowych z terenów górniczych w Polsce. Drgania te były spowodowane najintensywniejszymi wstrząsami górniczymi, jakie wystąpiły podczas podziemnej eksploatacji kopalni węgla kamiennego i rud miedzi w Polsce. Wyniki pomiarów in-situ tych drgań porównano z zapisami drgań z wybranych trzęsień ziemi. Szczególną uwagę zwrócono na wartości wskaźnika PGA/PGV, a także różnice charakteryzujące drgania powierzchniowe indukowane podziemną eksploatacją górniczą i wstrząsy sejsmiczne oraz czas trwania intensywnej fazy drgań. Następnie przedstawiono najczęściej stosowane metody obliczeń dynamicznych konstrukcji. W ostatniej części pracy zaprezentowano numeryczny model dynamiczny wybranej żelbetowej konstrukcji wieży wyciągowej