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Using graph theory for designing district metered areas in water supply network
Get PDFMany water distribution systems (WDS) have high percentage of non revenue water (NRW). In order to decrease the volume of NRW, district metered areas (DMAs) are introduced, where hydraulic parameters such as pressure and flow are measured. Knowing the volume of inlet water into the DMA and the volume of revenue water at the demand nodes, it is easy to calculate the volume of NRW. Dividing WDS into different DMAs enables the water management utilities faster identification of water losses and effective control over the whole system. However, there are also some negative effects such as lower pressure and problems related to water quality. The objective is to divide WDS into DMAs in such way that the hydraulic conditions don’t get worse. Many of known methods are limited to small or skeletioned WDS. Therefore our aim is to find a fast and effective algorithm for partitioning complex networks. Among several algorithms the algorithm for spectral partitioning was selected. Some hydraulic parameters are included in the method as input data in order to generate hydraulically suitable solutions. Numerous solutions are obtained, among which the optimal is selected. All of them are tested with program EPANET 2.0 and MATLAB 2015 using the EPANET Programmer Toolkit. The proposed method was also tested on a real case study
Software for the design of beam to column connections according to the component method
Get PDFThis master thesis presents the component method for design of beam-to-column moment resisting conection. By dividing the connection into components and by determining characteristics of these components it is possible to determine mechanical response in sense of resistance, rotational stiffenes and rotational capacity of the connection. The procedure of evaluating the connection by its components is called component method for designing connections.\ud
The component method can be used for steel grades up to and including S460. In general it is not limited to any type of cross-section or for any kind of connection configuration. The component method is a result of many investigations across the world and is validated by tests of connections.\ud
That is the reason why the component method fairly easy allows good prediction of nonlinear behavior of moment resisting connections. The main goal of this master thesis was to develop program KMrup for calculating resistance and\ud
rotational stiffness of moment resisting connections using component method. Essentially KMrup is developed for calculating moment resisting beam to column connection with extended end plate. With adapted data input and proper reading of the results, the use of the program can be extended to use on different types of connection configurations (beam to beam, two sided beam to column connection). Software is written in web programming languages, which means that it is easy to use on practically\ud
any device that can browse the internet. KMrup requires internet browsing program The program is validated by four connection configurations that were calculated by commercial\ud
program SCIA Engineer and with results found in literatur
Energy balance before and after partial renovation of residential building`s thermal envelope
Get PDFIn this thesis, the energy balance of residential building with five individual units in Velenje, was calculated. The energy balance was calculated for the situation before the renovation of building's heat envelope, for the actual situation after the completion of the reconstruction of bulding's heat envelope and for the two examples of possible additional improvements of the current situation. In reality, the building's heat envelope was only partly renovated, covering the four of the five individual units. For all numerical examples, the heat required for heating was calculated. These results were compared with data on actual consumption of heat, which has been obtained for a period of three years before and one year after the renovation of building's envelope. \ud
Calculation of the necessary heat for heating was made in accordance with the methodology dictated by legal rules in the field of energy efficiency in buildings. Policy on efficient use of energy in buldings (PURES 2010) was therefore presented in the thesis. Comparison of actual and calculated heat consumption has shown minor variations which are most likely due to imprecise inputs such as ventilation, thermal transmittance of windows and doors, passage of the solar radiation through windows, internal gains and other data entered, which was based on engineering estimates, because the exact values were not available. Nevertheless, the final results were comparable
Involving the public in the procedure of the creation of detailed plan of national importance
Get PDFThe master thesis examines the field of public participation in the process of creation of the national spatial plans. The first theoretical parts include chapters which examine social and legal framework of involvement of the public in the process of creation of national spatial plans. They are followed by a general chapter on communication, whic is an essential part for the integration of the public. The methodological part includes the presentation of the approach which through participant observation and analysis of individual cases extracts the framework model of integrating the public in practice. The model is presented from the initiative to the acceptance phase of the national spatial plan. At the end, the key principles of involving the public that should be taken into account while preparing each national spatial plan, are presented
Valuation of vacant building land based on market standard ground values
Get PDFThe purpose of this Master Thesis is to create an evaluation system of undeveloped building land, which will allow objective evaluation of the market value of building land. We have set ourselves the following research hypothesis: the generalized market value of building land, estimated to meet the needs of mass valuation, is not applicable to individual valuation of building lands in Slovenia, because it does not reflect the situation on the market of building land. Therefore, in Slovenia we need to establish a system of an individual valuation of building land, based on the market standard ground values of building land.\ud
For the purposes of research, we obtained, processed and analyzed data on completed transactions with building land on the applied area of the Municipality of Maribor in the period from 2007 to the end of 2014. We adjusted the acquired data on completed transactions on 31 12 2014 and eliminated the differences, caussed by different time of sale. We have created value zones by using the modified method of leaders. The adequacy of formed zones has been checked by comparing the coefficients of variation and execution of t-tests with which we verified differences of created zones. We have determined the reference building land, which has properties that are on the applied area most represented. Range of factors that affect the value of building land has been determined based on a survey of the professional public. With multiple regression analysis, we have checked which factors in each zone affected the value of building land. Standard ground values have been determined by a statistical method and its suitability was checked by intersubjective methods. In order to verify the adequacy of zones, the "Zielbaum" method or branched diagram after Aurnhammer procedure has been used. We have found that the standard ground value is properly defined by using the statistical methods. We have designed the coefficients for the conversion for variable area of building land in the value zone three. The survey has shown that the existing system of individual evaluation does not prohibit indirect valuation through market comparisons, which may also include the evaluation with the help of market standard ground values. It turns out that the derived market standard ground values are appropriate basis for carrying out individual evaluations of building land. We have found out that derived standard ground values in the applied area of Municipality of Maribor differ from the generalized market values
Tools for calculating the resistance of metal dowel-type connections of timber structures
Get PDFWithin the thesis I made a computer program created in the developer mode of Microsoft Excel program. The programming language used is called Visual Basic (VBA). Program can calculate load-carrying capacity of metal dowel-type fasteners such as nails, screws, bolts and dowels in a\ud
different type of single shear, double shear and some multiple shear timber connections. Calculations are based on Johansens’s yield theory which is slightly modified by Eurocode 5. First part of thesis describes Johansen’s equations and their application in Eurocode 5, the second part describes program operation and the equations used for each type of fastener
Fire resistance of cross - laminated timber elements
Get PDFThesis discusses methods for determining fire resistance of cross-laminated timber elements. Two different methods are presented, one according to EN 1995-1-2 and one according to CLT Handbook. Procedures of numerical modelling of cross-laminated elements are presented as well. Based on reports of experimental analyses, where some of them were made in real scale, comments, corrections and findings are offered. It appears that when determining fire resistance according to standard EN 1995-1-2, zero-strength layer d0 and charring depth dchar are most questionable. Indirect difficulty with crosslaminated elements is delamination phenomenon, and with latter connected numerical modelling and integration of phenomenon in current calculation methods, that are still relatively inaccurate. Specific problem is the determination of the critical temperature at which the glue separates and therefore lamination occurs as well as determination of higher degree of charred wood that occurs due to delamination. The last chapter presents the essential part of the thesis. In this chapter, parametric study for determining fire resistances of CLT slab according to European EN 1995-1-2 and Canadian CLT Handbook is performed. Parametric study discusses the effects of different sizes of openings and size of fire compartment where development of parametric fire is determined according to EN 1991-1-2. It was found out that fire limited to solely one room does not cause failure of the CLT slab, but in the case if fire progresses to entire apartment, fire would cause failure of the CLT element. Last part of the parametric study discusses deviation between both methods for determining the standard fire resistance of CLT elements. In the study influence of varying number of layers and length of CLT plate is compared. Comparison showed that more conservative results are obtained with CLT Handbook method
Mechanical response of curved timber beams with variable height under fire conditions
Get PDFThe thesis discusses the behaviour of a curved and tapered timber beam exposed to fire. For this purpose a\ud
new three-phase numerical model for the geometrical and material non-linear fire analysis is developed.\ud
In the first phase, the development of the gas temperature with time, within the fire compartment is\ud
determined. New mathematical and numerical model to determine the coupled heat and moisture transfer\ud
in timber exposed to fire is introduced in the second phase. The model accounts for the transfer of\ud
bound water, water vapour and air, coupled with the heat transfer. The main novelties of the model\ud
are: (i) the bound water transfer is refined by including the Soret e�ect, (ii) a modified description of\ud
sorption applicable for the temperatures above the boiling point of water is given, (iii) a moving boundary\ud
surface to prescribe water vapour flux and pressure at the contact between the unburned timber and the\ud
char layer is introduced. The system of governing di�erential equations is solved by the finite element\ud
method developed in the Matlab® environment. The basic unknowns of the model are: the temperature,\ud
the gas pressure, the water vapour and the bound water concentration. After validating the model and\ud
conducting parametric studies, the following conclusions can be given: (i) the model accurately predicts\ud
both the temperature field and the charring depth, (ii) the higher initial moisture content results in a slower\ud
development of temperatures, (iii) a significant e�ect of bound water di�usion on the total moisture\ud
content is shown and (iv) the influence of the convective heat transfer on the temperature distribution is\ud
negligible. In the third phase, a mechanical model to determine the stress–strain state of a curved and\ud
tapered timber beam exposed to fire is presented. The Reissner geometrically exact planar beam model is\ud
employed. Membrane, shear and flexural deformations of the beam are accounted for. The finite element\ud
method is used to solve the system of the governing non-linear equations. By validating and verifying the\ud
model it can be concluded that the model is very accurate and therefore suitable for the fire analysis of\ud
a curved and tapered timber beam. Beside the three-phase numerical model, the thesis also extensively\ud
discusses the methodology for estimating reliability of a timber beam exposed to fire, thus giving a firm\ud
basis for the modern performance based approach aiming at introducing uncertainties in the fire analysis
Consolidation of detached plaster layers of mural paintings with non-structural grouting
Get PDFIn this doctoral thesis the development of compatible injection grouts based on hydrated lime for non-structural consolidation of detached plaster layers of decorative architectural surfaces (mural paintings) is studied. A review of Slovenian and international conservation practices of re-attachment interventions of historical plaster layers is given, which has resulted in well-defined requirements for injection grouts that must be compatible with historical renderings in the chemical, physical and mechanical aspects. At the same time, the injection grouts had to assure good working properties in the fresh state, evaluated according properties such as fluidity, injectability, water retention, minimal shrinkage, stability, etc. Injection grouts were developed in several phases. In the framework of preliminary research 9 different injection grouts were designed. Volume stability of the injection grouts was selected as a criterion for the selection of compositions used for further researches (17 injection grouts). Injection grouts were designed based on mineral binder and filler (hydrated lime and inert limestone filler), ultra light filler (for weight reduction), tuff as puccolan additive (to increase the mechanical properties) and chemical admixture (PCE and PPh superplasticizers) to reduce the water content. The first selected measure to increase the volumetric stability of grout mixtures was the decrease of the binder to filler ratio. The second measure was the use of superplasticizer to reduce the water content for the required workability. Furthermore, the research of grout mixtures was divided into several steps by eliminating the mixtures with poor properties (not reaching the requirements). In the framework of the research work, special models have been developed – models with air pockets and sandwiches simulating the detached plaster layers and allowing additional research of significant properties, such as adhesive strength. The grout mixtures were tested following the modified standard tests specially adapted for non-structural grouts. Grout mixtures L1 S3 PCE and L1 S2B1 PCE have proved to possess the most optimal combinations of key properties. Both mixtures have good volumetric stability with minimal shrinkage, and good water retention and injectability with dry and pre–wetted crushed lime mortar columns. Their mechanical and physical properties are within the range of historical plasters and provide good adhesion in the case of 2 mm high air pockets. Moreover, accelerated ageing showed that mixture L1 S2B1 PCE is more durable under various climatic influences in combination with distilled water or NaCl. Therefore, mixture L1 S2B1 PCE was selected for stabilizing the detached plaster layers of the selected mural painting
Low-flow analysis of stream flows in Slovenia using DFLOW software
Get PDFThe calculation of low flows is crucial for monitoring streams and ensuring their quality, because they\ud
are habitat for many animals and plants. There is a number of different indices for calculation of low\ud
flows, such as flow duration curve, streamflow deficit, base flow index, ninety-five percentile flow Q95\ud
mean annual minima etc. In USA most commonly used methods for calculation of low flows are\ud
hydrological (xQy) and biological (xBy). Both methods can be implemented with DFLOW software.\ud
Hydrological method is statistical, biological one is empirical and uses aquatic life water quality\ud
criteria directly for its implementation. Criteria are expressed as two concentrations, instead of one, so\ud
that criteria can more exactly reflect toxicological and practical realities. The two concentrations are\ud
CCC, which provides the highest concentration of pollutants that could be maintained indefinitely in\ud
the stream and CMC, which determines maximum concentration of pollutants in the stream.\ud
In graduation thesis calculations of low flows and excursions with DFLOW sofware are conducted for\ud
56 Slovenian gauging stations. For calculated flows 4B3, 7Q10, 1B3 and 1Q10 an analysis and\ud
comparison with calculated Q95 were made. It has turned out that the calculated flows with software\ud
DFLOW compared to Q95 are significantly lower. For 15 selected gauging stations a comparison with\ud
ecologically acceptable flow by the Slovenian methodology and methods of selected European\ud
countries was also made. The smallest difference have occurred by comparison of flows 4B3, 7Q10,\ud
1B3 and 1Q10 with the return withdrawal by the Slovenian methodology and Austrain method Q361