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The behavior of reinforced concrete under long-term loading is an important topic when designing concrete structures. Creep and shrinkage of concrete and long-term deflections of concrete structures, mainly reinforced concrete beams, have been studied for many decades but because of the long-term nature of these tests, existing experiments are relatively scarce. More importantly, there are significant challenges when carrying out these tests. These include achieving optimal beam design to ensure a realistic stress distribution with a developed cracked state, measuring deflections from self-weight, adequately measuring elastic deflections and strains, and instantaneously applying the imposed load. The problem is exacerbated with the advent of sustainable structural concretes containing recycled and waste materials-green concretes; they possess specific properties and experimental results for these concretes are even scarcer. In this paper, an experimental setup, designed to test the structural behavior of reinforced concrete beams in a four-point bending test under long-term loading, is described. Six full-scale beams were produced from natural aggregate concrete, recycled aggregate concrete and high-volume fly ash concrete-two beams from each concrete type, one loaded after 7 and the other after 28 days. The load consisted of beam self-weight and imposed permanent load. The beam design procedure is explained, which enabled an adequate stress distribution and crack formation with a minimum imposed load. A method was developed to use geodetic equipment and measurements to determine the deflection from self-weight and a special support and loading structure were designed to enable instant imposed load application and the measurement of elastic deflections and strains. The complete test setup, equipment and procedure are explained and the advantages and deficiencies of this approach are discussed.

Prevailing climatic conditions and local topography can be classified as the most influential environmental factors that affect the spatial dispersion of pollutants emanating from industrial sources. In this study, the combined effects of these factors were considered with respect to terrain exposure in order to explain the complex, spatial trend of Arsenic (As) concentration that was atmospherically-deposited from one of the largest Copper Mining and Smelting Complexes in Europe, Bor in Serbia. Several exposure parameters were created and employed as spatial covariates within the so-called "Spline-Then-Krige" approach for producing maps of As concentration at three standard soil depth layers (0-5 cm, 5-15 cm and 15-30 cm). The exposure parameters were created to quantify two different aspects of terrain exposure: Geometrical (Proximity) and Topographical exposure. Regression analysis confirmed the presence of a significant statistical association between the As data and all exposure parameters. The trend model showed good overall accuracy explaining 52% of the variance in As data for the surface soil layer, 49% for the middle layer and 35% for the deepest layer. Relative importance analysis revealed the importance of considering a more general model that includes interactions between exposure parameters. The kriging interpolation improved, to some extent, the regression accuracy for all three layers with R-2 values ranging from 55% for the surface layer to the 36% for the deepest soil layer. The prediction maps show that As contamination levels are well above allowable Serbian agricultural concentration limits (As lt mg/kg) for approximately 78% of the mapping area, thereby indicating that long term smelting activity leaves significant consequences on soil even on deeper unexposed layers.

Geostatistical mapping of soil properties in 3D refers to the application of geostatisticalmethods to the soil data in order to produce maps of soil properties at different depths.Through two separate studies, this thesis elaborates on two different approaches for 3Dsoil mapping. At first, the well established Spline-Than-Krige approach for the mappingof soil pollutants atmospherically deposited from the copper smelting plant, was used. Inthe absence of the monitoring data, which can be used for a detailed characterization of theplume spreading process, this study was confined to the consideration of terrain exposureto explain spatial trend in arsenic distribution at different depths. This study aims toexplore the extent to which the commonly available information, such as the prevailingwind direction, or the location of the source of pollution, in combination with the digitalterrain model, can be used to quantify the terrain exposure, and hence to improve thespatial prediction of the arsenic concentration at several soil depths.Next, the innovative geostatistical approach to 3D mapping of soil properties, based onsoil profile data, was proposed. It provides the semi-automatic way for 3D modeling ofsoil variables, prediction over the regular grids (rasters) and also the evaluation of predictionaccuracy. Methodologically, this approach operates within the 3D regression krigingframework. 3D trend model is conceptualized as hierarchical or non-hierarchical linearinteraction model. This means that the model includes the interactions between the spatialcovariates and depth in the hiearchial or non-hierarchial manner. The trend modelingis based on the application of the penalized regression technique, lasso. The lasso usesa specific regularization penalty in a fitting procedure to enable the efficient parameterestimation and variable selection (including interaction terms) at the same time..., Geostatistiˇcko kartiranje zemljišta u 3D odnosi se na primenu geostatistiˇckih metoda nazemljišnim podacima u cilju izrade karata zemljišnih karakteristika jednog podruˇcja, kojese odnose na razliˇcite dubine zemljišta. U okviru dve nezavisne studije, ova doktorskadisertacija razmatra dva razliˇcita pristupa geostatistiˇckog modeliranja zemljišta u 3D. Uokviru prve studije, "Spline-Than-Krige" metod je koriš´cen za kartiranje koncentracijearsena u zemljištu, u blizini Rudarsko-topioniˇcarskog basena Bor, na tri razliˇcite dubine(0-5 cm, 5-15 cm i 15-30 cm). Dugogodišnje emitovanje nepreˇciš´cenih materija iz topionicerudnika u atmosferu, dovelo je do zagadjenja zemljišta u okolini, taloženjem štetnihmaterija nošenih vetrom. U odsustvu podataka kojima bi se detaljnije mogao opisati procesraspršivanja štetnih materija, ova studija se ograniˇcila na analizu izloženosti terenauticaju vetra, a time i procesu zagad¯enja. Predstavljen je inovativan pristup kvantifikacijiizloženosti terena izvoru zagad¯enja. Na osnovu opšte dostupnih podataka, kreirano jenekoliko parametara kojima se kvantifikuje geometrijska i topografska izloženost svaketacˇke terena izvoru zagad¯enja. Tako kreirani parametri, iskorišc´eni su za opisivanje prostornogtrenda koncentracije arsena na tri razliˇcite dubine. Definisani trendovi, koriš´ceni suu okviru regresionog kriginga, za prostornu predikciju. Na taj naˇcin pokušalo se odgovoritina pitanje, u kojoj meri, opšte dostupni podaci, kao što su pravac dominantnog vetraili poznavanje taˇcne lokacije izvora zagadjenja u kombinaciji sa digitalnim modelom terena,mogu biti iskoriš´ceni da bi se unapredila preciznost prostorne predikcije zemljišnihzagadjivaˇca, kako na površinskim slojevima tako i na ve´cim dubinama...

This paper presents the procedure of structure behaviour analysis and modelling applying the subspace method, which has been used in system identification but not in geodetic practice. This method enables the state space dynamic model parameters to be estimated. The equation error model has been used to form the dynamic system model. In addition, two pylons of the same bridge have been demonstrated to behave differently due to the position of the Sun. The entire system identification procedure has been demonstrated in modelling behaviour of the "Sloboda" bridge over the Danube pylon in direction of Novi Sad. The measurements were compiled during the bridge test load conducted in September 2005. The input signals subject to the analysis are the long-periodic signals: namely, the force in pylon cables and temperature. The output signals are pylon top displacements. The civil engineering experts' requirements called for identification of all displacements exceeding 10 mm. The pylon top position was determined by static GPS along with the 25- minute measurements per epoch.

Application of the open source software when resolving geodetic issues provides limitless possibilities. The present paper will showcase a methodology for setting out of engineering projects through a combination of GIS (Geographic Information System) software QGIS and R software environment. The link between QGIS and R had been established using Sextante toolbox, which significantly extends possibilities for a QGIS application, by establishing link to the other 'powerful' tools, such as R. Test example of land expropriation project shows the possibilities of the QGIS application for analytical elaboration of an expropriation zone, and R software package for automating setting out accuracy calculation.

Paper will present basic definitions and significance of implementation of information systems for facility maintenance, as well as terms Facility management (FM) and FM lifecycle. The main focus of this paper is on CAD and GIS integration within ArcGIS software in order to consolidate different data formats for creating unique information system for FM., U okviru rada daće se osnovne definicije i značaj primene informacionih sistema za potrebe održavanja objekata, objasniće se pojmovi Facility management i životni ciklus objekata. Akcenat u radu dat je integraciji CAD i GIS tehnologije u okviru softverskog paketa ArcGIS u cilju objedinjavanja različitih formata podataka radi kreiranja jedinstvenog informacionog sistema objekata.

In this paper we present a method for control of geometry of engineering facility by geodetic methods. Control of geometry can be performed by location, shape and size and shape only. Paper also presents all necessary surveying work for the successful control of geometry, but testing geometry of figures assumed estimation parameters of figures and application of linear hypothesis for the analysis of deviation from the assumed geometry. The testing procedure is elaborated through detailed examples of a straight line, and possibility of geodetic methods are given through an example of control the geometry of the reservoir for gasoline., U ovom radu je prikazan postupak kontrole geometrije inženjerskih objekata geodetskim metodama. Kontrola geometrije se obavlja po položaju, obliku i veličini ili samo obliku ispitivanog objekta. U radu su prikazani svi neophodni geodetski radovi za uspešnu kontrolu geometrije, ali je detaljno obrađeno samo testiranje geometrije, koje podrazumeva ocenjivanje parametara figura primenom linearnih hipoteza za analizu odstupanja od pretpostavljene geometrijske forme objekta. Postupak testiranja je detaljno prikazan kroz primere za pravu liniju, a mogućnosti geodetskih metoda su dati kroz primer kontrole geometrije rezervoara za motorni benzin.