This paper presents the slope stability analysis for the current as well as projected (final) geometry of waste dump Sandstone Open Pit “Osielec”. For the stability analysis six sections were selected. Then, the final geometry of the waste dump was designed and the stability analysis was conducted. On the basis of the analysis results the opportunities to improve the stability of the object were identified. The next issue addressed in the paper was to determine the proportion of the mixture containing mining and processing wastes, for which the waste dump remains stable. Stability calculations were carried out using Janbu method, which belongs to the limit equilibrium methods.
In recent years, we have witnessed very frequent natural disasters such as earthquakes, floods, landslides, storms and similar. In most cases, disasters are caused by geological factors, especially geobarriers. Geobarriers threaten the life and works of man or reduce the effectiveness of the construction and operation of technical works, or harm the environment by negative anthropogenic influences. An important task in assessing the technical and environmental aspects of particular engineering activity is to assess the impact of constructions on the production and protection of the environment. The important part of the environment is the geological environment. In this paper, we give an overview of geological factors of the environment and the way how they are illustrated in the engineering-geological maps made in Slovakia.
This study presents the results of calculations of the of thermo consolidation process of porous medium with the rheological Kelvin-Voigt skeleton, obtained numerically with the use of Flex.PDE. It is a continuation of the discussion on the phenomenon of thermal consolidation. A 3D problem considered boils down to solving the problem of the porous column filled with a liquid and treated by applying uniaxial compression load through a porous plate, allowing free flow of liquid from the center. To the sample affected by external lateral pressure. Numerical solution assumes compressing the sample at properly defined boundary conditions. The aim of this study was to describe the influence of external load and temperature gradient in the deformation tests for the case when the lateral surface is a good conductor of heat, and where the lateral surface of the sample does not conduct heat. The results obtained, in the context of further research, can also be used to determine the influence of other parameters of the state and model parameters on the process of thermo poroelasticity of the Biot model with rheological skeleton.
This work is only a preliminary study on the evaluation of geological engineering properties of loess area of Kraków. It has been expanded to include field tests (CPTU, DMT), which is an alternative to expensive and time-consuming laboratory tests. The field tests allow enough detail to track the variability of physical and mechanical properties of soils, but in many cases, provide too much information, because their interpretation is often based only on a qualitative analysis. Laboratory and field tests are complementary and should be continued in order to determine best the correlation between the measured values of the resistance probes (CPTU, DMT) and the results obtained from laboratory tests. This will provide new calculation formulas for the evaluation of geotechnical parameters of loess in situ.
Yielding support, commonly applied to secure dog headings, is made of carrying elements in the form of steel frames and friction props. Yielding capacity of this support is realized in frictional joints, which due to their geometry can be divided to straight and arch joints. Occurring in steel frames arch frictional joints are characterized with more complex loading state than straight joints used in friction props. In the article, there is presented an analysis of the state of stress and deformation of the arch frictional joint, which was carried out on the model of these joints using finite element method. The scope of the analysis included two methods of loading of arch frictional joint, namely its axial compression and bending. In both cases, joints were loaded dynamically with the impact of freely falling mass. Arch joints with and without passive pressure were submitted to an axial compression. Physical model of the frictional joint was developed on the basis of a system applied during the stand tests. To solve mathematical model an explicit integration method was used. As a result of analyses carried out, temporal courses of force transmitted through the frictional joint, and displacements of section sliding down were determined. On the basis of the temporal courses, dependences between maximum value of force transmitted through the frictional joint and the height from which the impact mass falls down were determined. Distributions of reduced stresses in elements of frictional joint were also determined and the state of deformation was described. In order to emphasize the difference between straight and arch frictional joints, also an analysis of internal forces in arch frictional joint depending on its geometrical parameters without and with passive pressure was presented.
The article is based on the results of uniaxial and triaxial compression tests, performed on Wustenzeller sandstone. An overview of the possible definitions of damage variable describing the process of damage development on the basis of various hypotheses has been presented in the first part of the article. In the main part of the article the author has presented the results of laboratory investigations, where the state of damage and its changes in rock samples under uniaxial and triaxial compression conditions were being observed. Using a modified procedure of triaxial tests, a definition of damage variable, determined on the basis of changes of volumetric stiffness of an examined rock, has been developed. Damage variable defined this way, in relation to a variable determined on the basis of axial stiffness changes, points to some anisotropy effects of damage phenomenon. The results obtained from both methods have been compared whereas the relations determining the evolution of damage variable in the loading process have been established.
The paper summarizes the reconstruction of the historical building erected in the 14th century, during the times of the residence of Grand Master of the Teutonic Order Winrich von Kniprode, currently referred to as the Latin School. It characterizes the location of the Latin School in the urban conservation area of the town of Malbork. The building is situated in the stretch of the buttressed brick escarpment on the Nogat River in the line of the historic defensive walls of Malbork. The paper also outlines the history of this building, constructed and managed by the municipal authorities of Malbork, which for a long time was a seat of a Patronage of Saint George and the Merchant Guild, and next, from the 16th century until 1864, the building housed a school where basic Latin was taught. Next, the situation of this historical monument in the 20th century is discussed. In the next part of the paper, the geological conditions of the site where the building was erected are discussed. The conducted archeological and architectural exploratory research related to the historical building with a particular emphasis on historic preservation and restoration works focusing on the building and its surroundings is presented and analyzed. Currently carried out design, construction and adaptation works allowing new functions to be embedded into this building are also discussed. The paper shows the benefits due to the realization of the reconstruction program of the degraded building of the Latin school in the historic quarter of the town. These activities are aimed at the conversion of the currently derelict building by means of embedding new functions into it. There are being designed, among others, an interactive educational center modern library, astronomical observatory, craft museum and multifunctional hall, allowing proper conditions to be created for the development of educational, artistic and tourism related activities in the reconstructed building. The reconstruction of the historical building is a positive response to its deterioration resulting from former activities and it will contribute to the improvement of the quality of cultural life of both local inhabitants and visitors.
Published Online: 14 Feb 2014 Page range: 93 - 108
Abstract
Abstract
The article presents an approach to evaluate and reduce the effort of the derivative pipeline in a water turbine of a hydroelectric power station in its vulnerable spots. Potential places of the biggest effort of the structure, as well as the coefficient of displacement and safety factor related to them were identified using FEM numerical method. Pipeline reinforcement was designed and made based on FEM analysis and non-destructive tests.
Published Online: 14 Feb 2014 Page range: 109 - 117
Abstract
Abstract
A number of synthetic pseudoacoustic impedance sections are presented in order to test the effectiveness of deconvolution process when random noise distorted the seismic traces. A simplified seismological model is created on the basis of geological data from Bytom Odrzański area in NW part of the Legnica-Głogów Copper District (LGOM). The synthetic sections are constructed for different noise levels. Acoustic impedance is one of the basic factors characterising physical features of rocks. The main idea is the inversion of seismic sections into pseudoacoustic impedance sections. All inhomogeneities of salt deposits must be predicted before the underground storage location is fixed. The accuracy and reliability of interpretation decreases when the noise in seismic data increases. It should be realised that the inversion procedure is not a unique process. So, modelling pseudoacoustic impedance sections is recommended for verification of the effectiveness of deconvolution process for the accuracy and reliability interpretation.
Published Online: 14 Feb 2014 Page range: 119 - 127
Abstract
Abstract
Within the boundaries of the Salt Mine “Kłodawa”, rock-salts and potassium-magnesium salts occur at different stratigraphic levels. The present article introduces strength-strain properties of white rock salt, building the nucleus of northeastern edge anticline, and pink rock salt that belongs to the series of youngest rock salt. On the grounds of the research on strength and strain parameters (uniaxial compressive and tensile strength, triaxial shear strength, modulus of elasticity and Poisson ratio) there is presented, in the article, variation of basic parameters determining geo-mechanical properties of rock salt in Kłodawa salt diapir.
Published Online: 14 Feb 2014 Page range: 129 - 141
Abstract
Abstract
Decrease of groundwater table level or decrease of buoyancy effects of groundwater is one of the most important landslide remediation measures. In Slovakia as well as in the world the horizontal drainage boreholes are often used for the landslide remediation. The article describes 40 years’ experience with use of the horizontal drainage boreholes in Slovakia, particularly in terms of their effectiveness and long-term functionality.
Published Online: 14 Feb 2014 Page range: 143 - 156
Abstract
Abstract
This article presents the impact of the retreat mining (i.e., involving an intended collapse of the excavation roof, subsequent to extraction) on the subsidence of the ground surface. The analysis was carried out for two areas of coal underground mining located in the Upper Silesian Coal Basin (Górnośląskie Zagłębie Węglowe). The assessment of the influence of exploitation on the ground surface was based on the results of geodetic measurements performed over a long period of time, whereas the land deformation prediction was made with the use of the EDNOPN program. The calculated and the predicted values were further compared, and the parameters of theory were determined. The results discussed in this paper have been shown by way of diagrams. The observed differences in the processes of vertical displacement were used in the analysis which took into account the degree to which the rock mass had been disturbed during the previous excavations, as well as the type of incumbent rock in the area under study.
Published Online: 14 Feb 2014 Page range: 157 - 182
Abstract
Abstract
The paper presents the first stage of research on a geostatistical hydrogeochemical 3D model dedicated to the horizontal and vertical spatial and time variation in the topographical, hydrological and quality parameters of underground water in the Kłodzko water intake area. The research covers the period 1977-2012. For this purpose various thematic databases, containing original data on coordinates X, Y (latitude and longitude) and Z (terrain elevation and time - years) and on regionalized variables, i.e., the underground water quality parameters in the Kłodzko water intake area determined for different analytical configurations (22 wells, 14 wells, 14 wells + 3 piezometers), were created. The data were subjected to spatial analyses using statistical methods. The input for the studies was the chemical determination of the quality parameters of underground water samples taken from the wells in the water intake area in different periods of time. Both archival data (acquired in the years 1977-1999, 1977-2011) and the latest data (collected in November 2011 and in January 2012) were analyzed. First, the underground water intake area with 22 wells was investigated. Then in order to assess the current quality of the underground water, 14 wells out of the 22 wells were selected for further chemical analyses and a collection siphon wall was included. Recently, three new piezometers were installed in the water intake area and so new water samples were taken, whereby the databases were supplemented with new chemical determinations. The variation in the topographical parameter (terrain elevation) and in the hydrogeological parameters: water abstraction level Z (with and without the land layout being taken into account) and the depth of occurrence of the water table, was examined. Subsequently, the variation in quality parameters was studied on the basis of data coming from 22 wells, then 14 wells and finally from 14 wells and 3 piezometers. The variation in: Fe, Mn, ammonium ions NH4 +, nitrite anion NO3 - and phosphate anion PO4 -3 content values, total organic carbon (TOC) C content, the pH reaction and temperature (°C) of the water was investigated. The basic statistics and distribution histograms of the topographical, hydrogeological and quality parameters (22 wells, 14 wells, 14 wells + 3 piezometers; the years: 1977-1999, 2011, 2011-2012) were estimated and detailed characteristics of the variation in the parameters in the whole underground water intake area over the years were obtained. Generally, the behaviour of the underground water quality parameters has been found to vary in space and time. Thanks to the multidirectional spatial analyses of the variation in the quality parameters in the Kłodzko underground water intake area some regularities in the variation in water quality have been identified.
Published Online: 14 Feb 2014 Page range: 183 - 194
Abstract
Abstract
Recognition of properties of the rock mass surrounding a mineral deposit is particularly important for the mining operations at greater depths. Since the rock mass is usually not homogeneous, and its parameters have characteristics of randomness, underground workings safety issue should always be analysed taking into account the dispersion of the values of these parameters around their mean values. In order to assess the impact of geotechnical parameters uncertainty on the excavation stability one uses the appropriate statistical approach. In this paper, by analysing successive combinations of geomechanical parameters of the rock in the measured range, we examined the effect of their variability on risk of underground excavation instability using response surface method.
Published Online: 14 Feb 2014 Page range: 195 - 207
Abstract
Abstract
Recently, there is an increasing need for accurate and rapid thermal measurement of soils. Within a variety of available methods a needle probe test is most widely used. The needle probe method was standardized for the measurement of thermal conductivity of soils and soft rocks. In the paper, two different interpretation methods of the needle probe test were used for determination of thermal conductivity of selected soils. The first method (ASTM D5334-05 Standard approach) takes into account only the data which are recorded during heating while the second approach is based on fitting the known analytical solution to the data obtained within both heating and cooling phases. The soil samples used were classified as clayey ones. Laboratory tests were performed using the KD2Pro thermal conductivity meter (Decagon Devices) with a TR-1 sensor. The main goal of the paper is to show that the selection of interpretation method is very important and may lead to significant differences in resulting thermal conductivities.
Published Online: 14 Feb 2014 Page range: 209 - 218
Abstract
Abstract
The paper deals with the problem of shape optimization of underground tunnel excavation. In the pioneering work of Sałustowicz, the elliptic shape was assumed a priori to be an optimal one and then a determination of suitable semi-axes ratio was only the question. Two cases were distinguished there: self-supporting excavation and excavation with the structural support. An evolutionary structural optimization (ESO) procedure, employed in 2005 to optimize shape of underground excavation, confirms the assumptions concerning the case of self-supporting excavations. The case of supported excavation is considered in the present work. Optimization procedure of the simulated annealing (SA) is incorporated in the study. An energetic optimality condition, formulated in the authors’ previous papers is also adopted. Itasca FLAC software is utilized in numerical examples. Four different in situ stress ratios are investigated. The numerical results obtained confirm that the optimal shape tends to be an ellipse. The semi-axes ratio demonstrates compliance with the assumptions already existing in literature.
Published Online: 14 Feb 2014 Page range: 219 - 232
Abstract
Abstract
The aim of the study was to analyze the loss of filtration stability of fine desert sands due to the air flow caused by temperature difference. The loss of stability induces the effect of so called “quick sands”. Therefore, the calculations of air filtration through the loose sand medium in dry desert climate are presented. FlexPDE v.6. software was used for numerical calculation based on FEM.
Published Online: 14 Feb 2014 Page range: 233 - 244
Abstract
Abstract
HDMR (High Dimensional Model Representation) is a relatively new method that is used to form response surface based on results obtained through laboratory experiments or through numerical calculations. So far the method has been used mainly in chemistry, although a few studies conducted in recent years show that it can be considered a useful tool in soil mechanics and foundation engineering. The subject matter of this paper is the application of HDMR method to reliability assessment of bearing capacity of layered soils. Madej’s method, widely recognized and used by Polish engineers, is applied to conduct the calculations. In the analysed case bearing capacity is not expressed by means of an explicit formula. To fit the approximate functions of bearing capacity, its values are calculated on a grid of points equally spread on ranges of variables. Finding the relation between input and output data is conducted by means of assessing each variable’s influence on response’s mean value within a given scope. Approximate functions have been used to calculate reliability indices by means of FORM, SORM and Monte Carlo methods.
Published Online: 14 Feb 2014 Page range: 245 - 258
Abstract
Abstract
The paper deals with the comparison of Biot’s model for saturated, porous soils with other simplified models used in dynamic analysis. The purpose of this paper is to determine some limits of validity of the various models. In order to do this a full set of governing, dynamic equations of Biot model and a series of simplifying models such as u-p simplification and quasi-static consolidation models are considered. These formulations are applied to a simple soil layer under periodic surface loading. A displacement of skeleton and a displacement of fluid are shown and compared with each model for various formulations.
This paper presents the slope stability analysis for the current as well as projected (final) geometry of waste dump Sandstone Open Pit “Osielec”. For the stability analysis six sections were selected. Then, the final geometry of the waste dump was designed and the stability analysis was conducted. On the basis of the analysis results the opportunities to improve the stability of the object were identified. The next issue addressed in the paper was to determine the proportion of the mixture containing mining and processing wastes, for which the waste dump remains stable. Stability calculations were carried out using Janbu method, which belongs to the limit equilibrium methods.
In recent years, we have witnessed very frequent natural disasters such as earthquakes, floods, landslides, storms and similar. In most cases, disasters are caused by geological factors, especially geobarriers. Geobarriers threaten the life and works of man or reduce the effectiveness of the construction and operation of technical works, or harm the environment by negative anthropogenic influences. An important task in assessing the technical and environmental aspects of particular engineering activity is to assess the impact of constructions on the production and protection of the environment. The important part of the environment is the geological environment. In this paper, we give an overview of geological factors of the environment and the way how they are illustrated in the engineering-geological maps made in Slovakia.
This study presents the results of calculations of the of thermo consolidation process of porous medium with the rheological Kelvin-Voigt skeleton, obtained numerically with the use of Flex.PDE. It is a continuation of the discussion on the phenomenon of thermal consolidation. A 3D problem considered boils down to solving the problem of the porous column filled with a liquid and treated by applying uniaxial compression load through a porous plate, allowing free flow of liquid from the center. To the sample affected by external lateral pressure. Numerical solution assumes compressing the sample at properly defined boundary conditions. The aim of this study was to describe the influence of external load and temperature gradient in the deformation tests for the case when the lateral surface is a good conductor of heat, and where the lateral surface of the sample does not conduct heat. The results obtained, in the context of further research, can also be used to determine the influence of other parameters of the state and model parameters on the process of thermo poroelasticity of the Biot model with rheological skeleton.
This work is only a preliminary study on the evaluation of geological engineering properties of loess area of Kraków. It has been expanded to include field tests (CPTU, DMT), which is an alternative to expensive and time-consuming laboratory tests. The field tests allow enough detail to track the variability of physical and mechanical properties of soils, but in many cases, provide too much information, because their interpretation is often based only on a qualitative analysis. Laboratory and field tests are complementary and should be continued in order to determine best the correlation between the measured values of the resistance probes (CPTU, DMT) and the results obtained from laboratory tests. This will provide new calculation formulas for the evaluation of geotechnical parameters of loess in situ.
Yielding support, commonly applied to secure dog headings, is made of carrying elements in the form of steel frames and friction props. Yielding capacity of this support is realized in frictional joints, which due to their geometry can be divided to straight and arch joints. Occurring in steel frames arch frictional joints are characterized with more complex loading state than straight joints used in friction props. In the article, there is presented an analysis of the state of stress and deformation of the arch frictional joint, which was carried out on the model of these joints using finite element method. The scope of the analysis included two methods of loading of arch frictional joint, namely its axial compression and bending. In both cases, joints were loaded dynamically with the impact of freely falling mass. Arch joints with and without passive pressure were submitted to an axial compression. Physical model of the frictional joint was developed on the basis of a system applied during the stand tests. To solve mathematical model an explicit integration method was used. As a result of analyses carried out, temporal courses of force transmitted through the frictional joint, and displacements of section sliding down were determined. On the basis of the temporal courses, dependences between maximum value of force transmitted through the frictional joint and the height from which the impact mass falls down were determined. Distributions of reduced stresses in elements of frictional joint were also determined and the state of deformation was described. In order to emphasize the difference between straight and arch frictional joints, also an analysis of internal forces in arch frictional joint depending on its geometrical parameters without and with passive pressure was presented.
The article is based on the results of uniaxial and triaxial compression tests, performed on Wustenzeller sandstone. An overview of the possible definitions of damage variable describing the process of damage development on the basis of various hypotheses has been presented in the first part of the article. In the main part of the article the author has presented the results of laboratory investigations, where the state of damage and its changes in rock samples under uniaxial and triaxial compression conditions were being observed. Using a modified procedure of triaxial tests, a definition of damage variable, determined on the basis of changes of volumetric stiffness of an examined rock, has been developed. Damage variable defined this way, in relation to a variable determined on the basis of axial stiffness changes, points to some anisotropy effects of damage phenomenon. The results obtained from both methods have been compared whereas the relations determining the evolution of damage variable in the loading process have been established.
The paper summarizes the reconstruction of the historical building erected in the 14th century, during the times of the residence of Grand Master of the Teutonic Order Winrich von Kniprode, currently referred to as the Latin School. It characterizes the location of the Latin School in the urban conservation area of the town of Malbork. The building is situated in the stretch of the buttressed brick escarpment on the Nogat River in the line of the historic defensive walls of Malbork. The paper also outlines the history of this building, constructed and managed by the municipal authorities of Malbork, which for a long time was a seat of a Patronage of Saint George and the Merchant Guild, and next, from the 16th century until 1864, the building housed a school where basic Latin was taught. Next, the situation of this historical monument in the 20th century is discussed. In the next part of the paper, the geological conditions of the site where the building was erected are discussed. The conducted archeological and architectural exploratory research related to the historical building with a particular emphasis on historic preservation and restoration works focusing on the building and its surroundings is presented and analyzed. Currently carried out design, construction and adaptation works allowing new functions to be embedded into this building are also discussed. The paper shows the benefits due to the realization of the reconstruction program of the degraded building of the Latin school in the historic quarter of the town. These activities are aimed at the conversion of the currently derelict building by means of embedding new functions into it. There are being designed, among others, an interactive educational center modern library, astronomical observatory, craft museum and multifunctional hall, allowing proper conditions to be created for the development of educational, artistic and tourism related activities in the reconstructed building. The reconstruction of the historical building is a positive response to its deterioration resulting from former activities and it will contribute to the improvement of the quality of cultural life of both local inhabitants and visitors.
The article presents an approach to evaluate and reduce the effort of the derivative pipeline in a water turbine of a hydroelectric power station in its vulnerable spots. Potential places of the biggest effort of the structure, as well as the coefficient of displacement and safety factor related to them were identified using FEM numerical method. Pipeline reinforcement was designed and made based on FEM analysis and non-destructive tests.
A number of synthetic pseudoacoustic impedance sections are presented in order to test the effectiveness of deconvolution process when random noise distorted the seismic traces. A simplified seismological model is created on the basis of geological data from Bytom Odrzański area in NW part of the Legnica-Głogów Copper District (LGOM). The synthetic sections are constructed for different noise levels. Acoustic impedance is one of the basic factors characterising physical features of rocks. The main idea is the inversion of seismic sections into pseudoacoustic impedance sections. All inhomogeneities of salt deposits must be predicted before the underground storage location is fixed. The accuracy and reliability of interpretation decreases when the noise in seismic data increases. It should be realised that the inversion procedure is not a unique process. So, modelling pseudoacoustic impedance sections is recommended for verification of the effectiveness of deconvolution process for the accuracy and reliability interpretation.
Within the boundaries of the Salt Mine “Kłodawa”, rock-salts and potassium-magnesium salts occur at different stratigraphic levels. The present article introduces strength-strain properties of white rock salt, building the nucleus of northeastern edge anticline, and pink rock salt that belongs to the series of youngest rock salt. On the grounds of the research on strength and strain parameters (uniaxial compressive and tensile strength, triaxial shear strength, modulus of elasticity and Poisson ratio) there is presented, in the article, variation of basic parameters determining geo-mechanical properties of rock salt in Kłodawa salt diapir.
Decrease of groundwater table level or decrease of buoyancy effects of groundwater is one of the most important landslide remediation measures. In Slovakia as well as in the world the horizontal drainage boreholes are often used for the landslide remediation. The article describes 40 years’ experience with use of the horizontal drainage boreholes in Slovakia, particularly in terms of their effectiveness and long-term functionality.
This article presents the impact of the retreat mining (i.e., involving an intended collapse of the excavation roof, subsequent to extraction) on the subsidence of the ground surface. The analysis was carried out for two areas of coal underground mining located in the Upper Silesian Coal Basin (Górnośląskie Zagłębie Węglowe). The assessment of the influence of exploitation on the ground surface was based on the results of geodetic measurements performed over a long period of time, whereas the land deformation prediction was made with the use of the EDNOPN program. The calculated and the predicted values were further compared, and the parameters of theory were determined. The results discussed in this paper have been shown by way of diagrams. The observed differences in the processes of vertical displacement were used in the analysis which took into account the degree to which the rock mass had been disturbed during the previous excavations, as well as the type of incumbent rock in the area under study.
The paper presents the first stage of research on a geostatistical hydrogeochemical 3D model dedicated to the horizontal and vertical spatial and time variation in the topographical, hydrological and quality parameters of underground water in the Kłodzko water intake area. The research covers the period 1977-2012. For this purpose various thematic databases, containing original data on coordinates X, Y (latitude and longitude) and Z (terrain elevation and time - years) and on regionalized variables, i.e., the underground water quality parameters in the Kłodzko water intake area determined for different analytical configurations (22 wells, 14 wells, 14 wells + 3 piezometers), were created. The data were subjected to spatial analyses using statistical methods. The input for the studies was the chemical determination of the quality parameters of underground water samples taken from the wells in the water intake area in different periods of time. Both archival data (acquired in the years 1977-1999, 1977-2011) and the latest data (collected in November 2011 and in January 2012) were analyzed. First, the underground water intake area with 22 wells was investigated. Then in order to assess the current quality of the underground water, 14 wells out of the 22 wells were selected for further chemical analyses and a collection siphon wall was included. Recently, three new piezometers were installed in the water intake area and so new water samples were taken, whereby the databases were supplemented with new chemical determinations. The variation in the topographical parameter (terrain elevation) and in the hydrogeological parameters: water abstraction level Z (with and without the land layout being taken into account) and the depth of occurrence of the water table, was examined. Subsequently, the variation in quality parameters was studied on the basis of data coming from 22 wells, then 14 wells and finally from 14 wells and 3 piezometers. The variation in: Fe, Mn, ammonium ions NH4 +, nitrite anion NO3 - and phosphate anion PO4 -3 content values, total organic carbon (TOC) C content, the pH reaction and temperature (°C) of the water was investigated. The basic statistics and distribution histograms of the topographical, hydrogeological and quality parameters (22 wells, 14 wells, 14 wells + 3 piezometers; the years: 1977-1999, 2011, 2011-2012) were estimated and detailed characteristics of the variation in the parameters in the whole underground water intake area over the years were obtained. Generally, the behaviour of the underground water quality parameters has been found to vary in space and time. Thanks to the multidirectional spatial analyses of the variation in the quality parameters in the Kłodzko underground water intake area some regularities in the variation in water quality have been identified.
Recognition of properties of the rock mass surrounding a mineral deposit is particularly important for the mining operations at greater depths. Since the rock mass is usually not homogeneous, and its parameters have characteristics of randomness, underground workings safety issue should always be analysed taking into account the dispersion of the values of these parameters around their mean values. In order to assess the impact of geotechnical parameters uncertainty on the excavation stability one uses the appropriate statistical approach. In this paper, by analysing successive combinations of geomechanical parameters of the rock in the measured range, we examined the effect of their variability on risk of underground excavation instability using response surface method.
Recently, there is an increasing need for accurate and rapid thermal measurement of soils. Within a variety of available methods a needle probe test is most widely used. The needle probe method was standardized for the measurement of thermal conductivity of soils and soft rocks. In the paper, two different interpretation methods of the needle probe test were used for determination of thermal conductivity of selected soils. The first method (ASTM D5334-05 Standard approach) takes into account only the data which are recorded during heating while the second approach is based on fitting the known analytical solution to the data obtained within both heating and cooling phases. The soil samples used were classified as clayey ones. Laboratory tests were performed using the KD2Pro thermal conductivity meter (Decagon Devices) with a TR-1 sensor. The main goal of the paper is to show that the selection of interpretation method is very important and may lead to significant differences in resulting thermal conductivities.
The paper deals with the problem of shape optimization of underground tunnel excavation. In the pioneering work of Sałustowicz, the elliptic shape was assumed a priori to be an optimal one and then a determination of suitable semi-axes ratio was only the question. Two cases were distinguished there: self-supporting excavation and excavation with the structural support. An evolutionary structural optimization (ESO) procedure, employed in 2005 to optimize shape of underground excavation, confirms the assumptions concerning the case of self-supporting excavations. The case of supported excavation is considered in the present work. Optimization procedure of the simulated annealing (SA) is incorporated in the study. An energetic optimality condition, formulated in the authors’ previous papers is also adopted. Itasca FLAC software is utilized in numerical examples. Four different in situ stress ratios are investigated. The numerical results obtained confirm that the optimal shape tends to be an ellipse. The semi-axes ratio demonstrates compliance with the assumptions already existing in literature.
The aim of the study was to analyze the loss of filtration stability of fine desert sands due to the air flow caused by temperature difference. The loss of stability induces the effect of so called “quick sands”. Therefore, the calculations of air filtration through the loose sand medium in dry desert climate are presented. FlexPDE v.6. software was used for numerical calculation based on FEM.
HDMR (High Dimensional Model Representation) is a relatively new method that is used to form response surface based on results obtained through laboratory experiments or through numerical calculations. So far the method has been used mainly in chemistry, although a few studies conducted in recent years show that it can be considered a useful tool in soil mechanics and foundation engineering. The subject matter of this paper is the application of HDMR method to reliability assessment of bearing capacity of layered soils. Madej’s method, widely recognized and used by Polish engineers, is applied to conduct the calculations. In the analysed case bearing capacity is not expressed by means of an explicit formula. To fit the approximate functions of bearing capacity, its values are calculated on a grid of points equally spread on ranges of variables. Finding the relation between input and output data is conducted by means of assessing each variable’s influence on response’s mean value within a given scope. Approximate functions have been used to calculate reliability indices by means of FORM, SORM and Monte Carlo methods.
The paper deals with the comparison of Biot’s model for saturated, porous soils with other simplified models used in dynamic analysis. The purpose of this paper is to determine some limits of validity of the various models. In order to do this a full set of governing, dynamic equations of Biot model and a series of simplifying models such as u-p simplification and quasi-static consolidation models are considered. These formulations are applied to a simple soil layer under periodic surface loading. A displacement of skeleton and a displacement of fluid are shown and compared with each model for various formulations.