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Validation of Building Energy Modeling Tools for a Residential Building in Brasov Area-Romania

5. REFERENCES [1] Emily M. Ryan, Thomas F. Sanquist, (2012), Validation of building energy modeling tools under idealized and realistic conditions. Energy and Buildings 47 , pp 375–382 [2] P. Hoes, et al. (2009), User behavior in whole building simulation, Energy and Buildings 41 , pp. 295–302 [3] C.M. Clevenger, J. Haymaker, (2006), The impact of the building occupant on energy modeling simulations, in: Computing and Decision Making in Civil and Building Engineering, International Society for Computing in Civil and Building Engineering

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Effective Friction Angle Of Deltaic Soils In The Vistula Marshlands

.5°. The CD triaxial tests on organic silt confirmed the updated Robertson’s (2016) classification as a practical tool for qualitative description of soil behaviour type (SBT). Acknowledgements The research is supported by the National Centre for Research and Development grant PBS3/B2/18/2015. Some of the geotechnical data was provided by the General Directorate for National Roads and Motorways in Poland. References [1] Ajlouni, M.A. 2000. Geotechnical properties of peat and related engineering problems. Ph.D. thesis, Univ. of Illinois at Urbana

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X-Ray Microtomography (μCT) as a Useful Tool for Visualization and Interpretation of Shear Strength Test Results

Abstract

The paper demonstrates the applicability of X-ray microtomography (ìCT) to analysis of the results of shear strength examinations of clayey soils. The method of X-ray three-dimensional imaging offers new possibilities in soil testing. The work focuses on a non-destructive method of evaluation of specimen quality used in shear tests and mechanical behavior of soil. The paper presents the results of examination of 4 selected clayey soils. Specimens prepared for the triaxial test have been scanned using ìCT before and after the triaxial compression tests. The shear strength parameters of the soils have been estimated. Changes in soil structure caused by compression and shear failure have been presented as visualizations of the samples tested. This allowed for improved interpretation and evaluation of soil strength parameters and recognition of pre-existing fissures and the exact mode of failure. Basic geometrical parameters have been determined for selected cross-sections of specimens after failure. The test results indicate the utility of the method applied in soil testing.

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Technical Note. The Concept of a Computer System for Interpretation of Tight Rocks Using X-Ray Computed Tomography Results

] KRAKOWSKA P., DOHNALIK M., JARZYNA J., WAWRZYNIAK- -GUZ K., Computed X-ray microtomography as the useful tool in petrophysics: A case study of tight carbonates Modryn formation from Poland, Journal of Natural Gas Science and Engineering, 2016, 31, 67-75. [15] KRAKOWSKA P., MADEJSKI P., JARZYNA J., Permeability estimation using CFD modeling in tight Carboniferous sandstone, EAGE EartDoc publishing, 76th EAGE Conference & Exhibition 2014, 16-19 June, Amsterdam, Holandia, 2014, DOI: 10.3997/2214-4609.20141607, Th P06 05, 1-5. [16] KRAKOWSKA P

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Application of Genetic Algorithms for the Estimation of Hydraulic Conductivity

algorithms are a highly effective tool for automatic analysis, based on simple rules and simultaneous calibration of all the parameters. It shows how to determine the basic parameters of the models using the example of the Biot model. The presented paper is a continuation and development of research concerning the determination of the parameters of complex rheological models [ 9 , 11 ]. 2.1 Mathematical model of the porous medium (Biot’s model) The classical constitutive relations for a poroelastic body in isothermal problems were given by [ 14 ]. The effective

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RELIABILITY ASSESSMENT OF BEARING CAPACITY OF LAYERED SOILS USING HIGH DIMENSIONAL MODEL REPRESENTATION (HDMR)

Representation and its application varieties, Tools for Mathematical Methods, Mathematical Research, St. Petersburg, Vol. 9, 2003, 146-159. [5] DITLEVSEN O., MADSEN H.O., Structural reliability Methods, John Wiley & Sons, Chichester, 1996. [6] FENTON G.A., GRIFFITHS D.V., Bearing capacity prediction of spatially random c - φ soils, Canadian Geotechnical Journal, 40(1), 2003, 545. [7] FENTON G.A., GRIFFITHS D.V., Risk Assessment in Geotechnical Engineering, John Wiley & Sons, New York, 2008. [8] HOHENBICHLER M

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NUMERICAL MODELLING FOR UNDERGROUND MINING RELATED GEOTECHNICAL ISSUES

Abstract

Issues presented in this work relate to geotechnical problems that are specific to the mining areas. The paper discusses the methodology of mathematical and numerical modeling of these problems. Examples contained in the paper include: predicting the influence of mining exploitation on a detached building and evaluating the effectiveness of the building protection with the trench. Possible applications of numerical modeling as a tool to aid the continuous monitoring of the building state during the exploitation have also been discussed

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Concrete surface evaluation based on the reflected TLS laser beam’s intensity image classification

Abstract

Dynamically developing terrestrial laser scanning technology (TLS)provides modern surveying tools, that is, scanning total stations and laser scanners. Owing to these instruments, periodic control surveys of concrete dams were performed as a part of geodetic monitoring yield point models characterised by quasicontinuity. Using the results of such measurements as a base, one can carry out a number of geometric analyses as well as acquire information for detailed analytical and calculative considerations.

The scanner, similar to total station, by determining distances and angles, identifies spatial coordinates (X, Y, Z) of the surveyed points. Registration of the reflected laser beam’s intensity value (Intensity) emitted by the scanner provides additional information on the surveyed object. Owing to high working speed and the large amount of the collected data, the scanners became an indispensable tool for geodesists.

The article assesses the possibility of application of terrestrial laser scanning in surveying changes in the surface of a concrete dam based on the experimental measurements. The condition of the dam’s downstream concrete wall was evaluated. The evaluation included changes in the surface’s roughness, cracks, seepage points, erosion caused by plant overgrowth and the degressive durability parameter of the used material (concrete).

The article presents an example of the application of the results of a laser scan in the assessment of the condition of a water dam’s external concrete surfaces. The results of experimental measurements were analysed – the results of a scan of the downstream concrete wall of a dam in Ecker (Germany) using two laser scanners characterised by different technical parameters, that is, laser wavelength (laser’s colour), range, definable point density, method of distance measurement – Leica C10, Z+F Imager 5006h. The measurement was carried out in the same weather conditions from the same sites of the test base.

The results of the measurements were analysed using, inter alia, statistical methods by defining template fields and supervised and unsupervised classification methods in reference to the selected fragments of the surface characterised by known concrete surface properties. Various classification algorithms were used. The obtained results make it possible to assess the suitability of the proposed methodology of evaluating the concrete surface’s condition and establish tool selection principles to match the practical application requirements.

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Numerical Model of Seepage Around Planned Water Reservoir in Kamieniec Ząbkowicki

Abstract

With a view to protecting areas lying near the Nysa Kłodzka river and in order to reduce flood wave in Wrocław Waterway System, construction of a water reservoir near Kamieniec Ząbkowicki is being planned. After analysing the hydrology and hydraulics of the river Nysa Kłodzka and the function of reservoirs in Kamieniec Ząbkowicki cascade, a numerical seepage model, based on finite element method (FEM) and taking into account bedrock geology, drainage design and dam sealing, has been proposed. Boussinesq’s mathematical model was used to calculate unconfined groundwater table and vector field of seepage velocity. Building a numerical terrain model and visualisation of the water table in GIS tools enabled presenting calculation results in 3-D space.

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Key Aspects of the Proper Formulation of the Model in Numerical Analysis of the Influence of Mining Exploitation on Buildings

Abstract

Numerical modelling is an important tool used to analyse various aspects of the impact of underground mining on existing and planned buildings. The interaction between the building and the soil is a complex matter and in many cases a numerical simulation is the only way of making calculations which will take into consideration the co–existence of a number of factors which have a significant influence on the solution. The complexity of the matter also makes it a difficult task to elaborate a proper mathematical model – it requires both a thorough knowledge of geologic conditions of the subsoil and the structural characteristics of the building.

This paper discusses the most important problems related to the construction of a mathematical model of a building-mining subsoil system. These problems have been collected on the basis of many years of experience the authors have in observing the surveying and tensometric deformations of the rock–mass and buildings as well as in mathematical and numerical modelling of the observed processes.

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