The impact of predicted vibrations from mining shocks on the viaduct – case study

The paper presents the results of dynamic calculations of a road viaduct subjected to loads resulting from mining shocks. The response spectrum method and the spatial MES model were used for the calculations. The calculations were carried out for predicted accelerations of ground vibrations. The results of calculations may in future be used in the assessment of dynamic resistance of similar structures

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

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

Transmission of transport vibrations from the ground to the building - case study

Transport vibrations are transmitted from the ground the foundations and building walls to the building and received by its construction and by people in the buildings. During the vibration of buildings, inertia forces generate an additional (apart from the static one) loading of the structure. In the diagnosis and design of buildings, these forces are taken into account by analyzing the requirements for stiffness and strength of the building structure. Exceedance of these requirements may lead to accelerated wear and even structural damages of the building. In this paper a simple relationship between ground and building vibration was made. The building chosen for analysis is light-weight wooden building located close to Cracow near Zakopianka road. What is worth noting that building is so called passive building. The excitation which was simulated on the dynamical polygon was car (bus) and truck lorry passages. The sensors were accelerations in three orthogonal directions, one sensor was placed about 2.5 m far from the building and the second on the foundation wall. The different types of excitation were compared and the conclusion from the analysis was made

Vibrations induced by the passage of trains at various speeds and their effect on the structural response of buildings - an experimental and numerical analysis

This paper presents a selection of vibration measurement results and analyses performed with regard to their harmfulness to residential buildings. The first part of the paper refers to the analysis of railway vibrations measured in situ at the foundation level of residential building. These vibration records were then used to assess the harmfulness of vibrations relating to each train speed. Assessment of the vibration harmfulness of the building was performed with an indicator of the perceptibility of vibration through a structure (WODB), according to the Polish standard. The second part of the study refers to the creation of dynamic models of buildings with the use of the ‘Diana’ software program and analysis of their responses to railway vibrations. The thresholds specified by the standard in any of the train speeds of up to 250 km/h were not exceeded. Nevertheless, propagation of vibrations induced by train passages and their effect on the structural response of buildings is a complex phenomenon. Without in situ measurements, it is hard to assess the impact of induced vibrations on buildings. As proven in the paper, a train moving on a track at various speeds does not uniformly make the vibration greater in each frequency band

Influence of duration of single dynamical events on the result of evaluation of human perception of vibration in buildings

The duration of vibration taken to the analysis influence on the result of evaluation of human perception of vibration. In this paper the relationship between the duration of individual events and the result of RMS and VDV analysis was investigated. The analysis was carried out on two buildings located close to Warsaw Metro line 1. The chosen buildings are typical masonry buildings located in the city center and subjected to three sources of traffic vibrations: subway, tramway and road. Evaluation of human perception of vibration was made using two different methods, the most popular, root mean squared method (RMS) and vibration dose value method (VDV). Methodology of these two methods is also described in the paper. The results from RMS and VDV methods are compared by using HPVR (human perception of vibration ratio) for RMS analysis. It is ratio discovered by prof. Stypula and it is very useful for the diagnosis. The conclusion from analysis are given