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The impact of laboratory simulated aging on bitumen properties at low temperatures
Get PDFResearch into the low temperature cracking in asphalt pavements is an important priority in asphalt laboratories worldwide. In such laboratories the low temperature cracking process is simulated on asphalt samples using several different types of tests. Due to the fact that the resistance of asphalt to low temperature cracking depends mainly on the used bitumen, it is assumed that this process can be indirectly predicted with knowledge about the realistic low temperature properties of bitumen. For many years the properties of bitumen at low temperatures have been determined based on the Fraass fracture temperatures. Since the Fraass breaking point test has several shortcomings, additional parameters like stiffness and creep rate were introduced in the Bending Beam Rheometer (BBR) method, which has been standardized but it is still not widely used. The characteristics of B 70/100, which is frequently used in Slovenia for asphalt production, has not been yet tested by this method.\ud
In the master’s thesis six samples of bitumen B 70/100 were extensively tested. The purpose of the study was to determine the impact of aging on the paving grade bitumen B 70/100 used in our region, and to propose criteria for bitumen quality based on evaluation of obtained test results. On neat bitumen the usual scope of bitumen tests (R&B, Penetration, Fraass) was performed as well as BBR and Dynamic Shear Rheometer (DSR) tests. These bitumens have been artificially aged with Rolling Thin Film Oven Test (RTFOT) method and all tests were repeated on short term aged bitumens. In the last step the six bitumens have been artificially aged with RTFOT and Pressure Ageing Vessel (PAV) method and then retested. In the thesis, the sensitivity to laboratory aging for six different samples of B 70/100 bitumens is presented and analyzed. The lowest and the highest ambient temperatures suitable for the six samples of B 70/100 were determined
Integral evaluation of playroom comfort in children day care centers
Get PDFThe majority of children spend their childhood in children day care centers, which represent the child's physical, biological and social environment. The purpose of this master thesis is to perform integral evaluation of comfort in twenty-five playrooms of eighteen Central-Slovenian children day care centers. Integral evaluation of comfort has been performed in four steps, which included measurements of selected parameters of comfort, as well as surveying of the employees. The comprehensive literature review was carried out in step 1 as we identified the problems and defined criteria for integral evaluation of comfort. In-situ measurements of the selected parameters of thermal and visual comfort, indoor air quality and acoustic comfort were carried out in step 2 (objective evaluation of comfort). In addition, the subjective evaluation of comfort was performed in step 3 on the basis of validated questionnaire. In the context of step 4 – integral evaluation of comfort – we compared the measured and calculated parameters of each comfort type, analyzed the possible relationship between various parameters of comfort in selected playrooms, compared the results of objective and subjective evaluation of comfort and exposed the key conclusions. Based on the implemented steps we formulated integral comfort scale. We suggested possible improvements for achieving comfortable and healthy conditions in children day care centers. We have found out that there are no researches, which would include integral evaluation of thermal, visual, acoustic comfort and indoor air quality of children day care centers. Consequently, we are the first who used integral evaluation of comfort approach in an educational institution. We have discovered that comfort in majority of day care centers is poor, while subjective evaluations of comfort parameters in playrooms were deviating from the objective ones. On the basis of integral comfort scale only two out of twentyfive playrooms were evaluated as integrally comfortable. Both, for new buildings as well as for the renovation of educational institutions, we suggest comprehensive measures, based on the presented integral evaluation of comfort
Establishment a database structure to evaluation and amortization public infrastructure
Get PDFThe present master's thesis deals with the establishment of a data system to be used for the assessment and calculation of depreciation of public service infrastructure for drinking water supply. The aim of collecting the funds for the restoration of the infrastructure network is to maintain the standard of supply and ensure the functional capacity of the infrastructure. The draft system to be used for the assessment and calculation of depreciation of public service infrastructure was designed by integrating the data from the cadastre of public service infrastructure and the existing data from the register of fixed assets. As it has been found during the course of writing the present thesis that the two sets of data are not consistent and that the data from the register of fixed assets do not show the real value of infrastructure or that the calculation of depreciation based on such register does not ensure a sufficient amount for the replacement of decrepit fixed assets, it is proposed that the assessment of public utility infrastructure be based on the data from the cadastre of public service infrastructure, which are presumed to be the most detailed and precise aggregated data on public utility infrastructure. It is proposed in the thesis that the purchase value of new infrastructure be assessed based on the data from the cadastre and the reference pricelist. A realistic assessment of the value of drinking water supply infrastructure facilitates the collection of sufficient depreciation funds and realistic pricing of drinking water supply. This in turn facilitates compliance with the requirements of EU directives (Commission Directive 2006/111/EC on the transparency of financial relations between Member States and public undertakings as well as on financial transparency within certain undertakings, Directive 2000/60/EC of the European Parliament and of the Council establishing a framework for Community action in the field of water policy) and with the fundamental environmental principles, i.e. the polluterpays principle and the coverage of all costs principle
Research of applying the HACCP principles to the water supply systems in Slovenia
Get PDFWholesome drinking water enables life and is one of the basic requirements of a healthy living environment. As it is a very important public good, handling with sources of drinking water, its supply and ensuring wholesome drinking water is very strictly regulated by the Slovenian and European laws. \ud
The requirements for drinking water are provided by the regulation Pravilnik o pitni vodi whichalso prescribes that internal control of drinking water must be established on the principles of HACCP system. HACCP is a preventive system that enables the identification of risks and critical control points and is providing a proper response to any existing risk factor. \ud
I examined the HACCP study of the water supply system Cerknica - Rakek, which is managed by JP Komunala Cerknica d.o.o.. I compared the irregularities identified by the\ud
health inspector and the results of analysis of drinking water in the 5-year period. The comparison showed a high proportion of inadequate analyses on the raw water and the\ud
maximum anomalies were identified in the risk analysis. This shows weakness of the HACCP study, where the risks have not been evaluated correctly, particulary not at the water source and in its hinterland.\ud
Better defined risks at water sources and in hinterland, better control and effective corrective procedure can reduce percent of inadequate analyses on the raw water and the need of water treatment before distribution to users
Influence of environment on the historical material with mineral binder
Get PDFDeterioration of historical materials with mineral binders in buildings of architectural heritage can be influenced by several different factors, which are often the result of changes in the environment where the buildings are located. In order to analyse the damages of these materials and the causes for their occurrence, three buildings of architectural heritage located in three different climatic zones were subjected to visual analysis and non-destructive testing using 3D microscopic system HIROX. In all the analysed buildings we found similar causes of the observed damages of architectural surfaces (biodegradation, salt crystallisation, moisture, etc.), regardless of the climatic zone. We also found that with the 3D microscopic system HIROX we can monitor opening/closing and progress of surface cracks, carry out analyses of the cracks, and also monitor the crystallization and dissolution of the surface salts, all these in-situ. On the samples of materials with mineral binder taken from the buildings we performed (where possible) petrographic analyses with an optical microscope and X-ray and TGA analysis in order to characterize historical mortars and determine the causes of damages. Reaction rims were observed on samples of masonry mortars from the Kolizej palace and they attracted our attention. In continuation of the doctoral dissertation we prepared replicas of analysed historical render-masonry-plaster composites and mortars for accelerated aging tests. To study the impact of crystallization and dissolution of salts on the render-masonry-plaster composites we developed accelerated test that allows continuous monitoring of the development and progression of damages with the 3D microscopic system HIROX. To study the reaction between mineral binder and dolomite aggregate grains observed in masonry mortar from the Kolizej palace, samples were prepared from six different mortars. As an aggregate we used inert limestone or selected dolomite grains, and as binder lime putty, lime putty with tuff or pure Portland cement was applied. Samples were exposed to different accelerated ageing conditions (a solution of deionised H2O or 1 M NaOH, and a temperature of 20 °C or 60 °C). On the samples mechanical tests and measurements of the modulus of elasticity, change in weight and length of the samples, as well as optical and electron microscopy (SEM) analyses were simultaneously carried out in prescribed time intervals up to one year. The results of the tests show that the alkaline carbonate reaction (ACR) occurs between the used dolomite aggregate and binder, and its progress influences changes of the mortars’ microstructure and thereby also changes of mechanical properties. ACR is manifested as a dedolomitisation process, which takes place in investigated mortars in different stages. The lowest level is dissolving process along the boundaries between dolomite crystals, called selective dedolomitisation. In the next stage reaction rims are formed. Under an optical microscope, the\ud
rims can be seen as a change in colour of sparite crystals from white to brown and under the SEM as a typical myrmekitic texture. Through the progress of the ACR, secondary calcite ("Ca halo") is formed in the binder, close to the modified parts of dolomite grains, and a "new phase" on the edge of the modified parts of dolomite grains. ACR occurs and progresses regardless of the binder type, but the dynamics of reactions and the formation of "Ca\ud
halo" and "new phase" depend on the type of binder. Diffusion of ions shows that the system is dynamic and changes with time. The temperature and selected aqueous solution influence the ACR progression
The impact of thermal bridges on energy consumption for heating in the case of primary school
Get PDFIn the case of Primary school Dobrova I checked what impact have actual thermal bridges on energy consumption for heating. From the plans of the building, I recorded all thermal bridges, which have affect on energy consumption. In standard SIST EN ISO 14683 I seek appropriate approximations to these thermal bridges. Then I made three simulations with the program TOST. In the first case I did not take thermal bridges into account. In the second case, I have taken them into account in a simplified manner and in the last case, I have taken them into account according to the SIST EN ISO 14683. Then I compared the results for all three cases with each other. Finally I made some steps how to reduce energy consumption. The results showed that the energy consumption due to thermal bridges increased by about 20%, comparing to SIST EN ISO 14683, regarding the case without taking them into account. In the case of a simplified method, the consumption increased by nearly 12%
The influence of new vertical datum at existing geodetic plans
Get PDFThe master's thesis brings attention to the procedures and results of the control of the elevation accuracy in selected geodetic plans. Elevations in the areas of geodetic plans were specified with the method of trigonometric levelling and with reference to benchmarks. The elevation accuracy in geodetic plans has been tested in order to evaluate the influence of the vertical datum changes in Slovenia. Our analysis includes 17 examples of geodetic plans from all over Slovenia. The thesis presents the results of the comparison between the elevations calculated to different vertical data with elevations in geodetic plans. Furthermore, a comparison of heights referring to vertical datums of Trieste, Koper and Amsterdam has been made
3D visualization traffic simulation with PTV Vissim
Get PDFThe thesis deals with the possibilities of 3D visualization of traffic simulation using the PTV Vissim\ud
software. In the first part of the thesis the concepts of simulation and visualization are described, as\ud
well as their role in the transport modelling. The importance of making visualization of traffic\ud
simulation models is presented. The visualization of traffic simulations serves as an aid when studying\ud
different transport solutions and in deciding which of them is the most optimal in a particular case. It\ud
also serves well as a tool for presentations of projects to the general public.\ud
The second part presents the possibilities of 3D visualization with the export of the transport model\ud
and the simulation results generated with the Vissim software into various graphics applications such\ud
as Autodesk 3ds Max and Google Earth. In addition, it presents the possibilities of 3D visualization of\ud
traffic models, enabled by the Vissim software tools.\ud
The final part discusses the creation of 3D visualization using the PTV Vissim 7 software. The\ud
visualization shows the flow of traffic in the parking garage next to the Planet Tuš shopping centre in\ud
Koper
Analysis of rail defects
Get PDFIn the initial part of the thesis we acquaint with rails, which are specially design steel beams - parts of\ud
the substructure of the railway line and the most important elements of the railway tracks. The beams\ud
perform the function of managing the acquisition of vehicles and direct traffic loads of transport\ud
assets. We presented the iron alloy – steel, which is the basic material for the production of rails. We\ud
describe in detail the development of the rail and the process of making rails through history. We\ud
presente constituent elements and characteristics of rails and describe the most typical types of rail\ud
defects and their properties.\ud
In the second part of the thesis we review existing data on the recorded rail defects on the whole\ud
railway network of the Republic of Slovenia and analyze defects in rails for each of the main routes.\ud
We compare the main routes according to the number of defects on the rails. Upon analysis and\ud
comparision, we conclude that the single-track lines stand out by the number of defects per track\ud
kilometer. We also observe that one double track lines stands out by the number of defects on rails\ud
considering the utilization of the line. The analysis of the Pearson correlation coefficient shows that\ud
the number of defects on rails linearly increases with decreasement of the temperatures. For other\ud
observed parameters (rail wear, rail age, speed on the track, axle load, the volume of traffic expressed\ud
in gross tonnage and gradient), the correlation analysis does not show any particular linear\ud
dependence
Assessment of the impact of climate change on the development of sport tourism in the Triglav National Park
Get PDFThe Triglav National Park is the only National Park in Slovenia. Due to the above average statistics of\ud
annual precipitation it is boasting with an exceptional wealth of water resources which are visible in a\ud
great number of various bodies of water, that not only represent a vital source of drinking water, but\ud
are also exploited in different economic purposes (e.g. tourism, energy industry, sports and recreation).\ud
The development of the above mentioned industries, which are linked to the hydrological circle, is\ud
also strongly linked with the future hydrological situation of the Triglav National Park. In recent\ud
decades the climate and hydrological situation has been undergoing some changes, also due to human\ud
impact. The impact of these changes vary by geographical location, but the North-western part of\ud
Slovenia, where the Triglav National Park is located, is characterized by an increase of air temperature\ud
and decrease of precipitation amount and snow depth cover. Sudden and extreme weather phenomena\ud
causing avalanches, erosion, floods, drought and other natural catastrophes are or will be more\ud
frequent. The following thesis present the impact of predicted climate changes on the development\ud
potential of those sporting and recreational activities within the boundaries of the National Park which\ud
are in any kind linked to the hydrological circle or all water forms (rain, snow, ice, water body). The\ud
representation of each individual sports or recreational activity is graphical displayed through GIS\ud
Tools. The core of the following thesis is a projection of selected influential climatological and\ud
hydrological variables within the Triglav National Park for the year 2030 through the process of\ud
extrapolation of the existing measurements and a subsequent evaluation of the impact of expected\ud
climate change on the development opportunities for the discussed sports activities. Based on the\ud
results of the analysis and given the expected guidelines of the climate changes propositions are given\ud
for further strategic sports and tourism tendencies of the Triglav National Park