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The thesis presents new solutions for the fractures problem in ornamental stone quarries which entails economic and material loses. The thesis aimed at developing methodologies and providing solutions for evaluation and production optimization of ornamental stone deposits. Ground Penetrating Radar (GPR) was selected, among several methods, as a fracture detection tool for this research. A combination of the use of a low frequency GPR antenna and laboratory rock tests for evaluation of an ornamental stone deposit showed encouraging results. Based on GPR survey, particularly high frequency antennas, a 3D deterministic fracture modeling approach was developed and implemented in several case studies of block and bench scales. A fracture index was proposed for deposit evaluation based on fracture detections from GPR survey. Additionally, an in-situ GPR test allowed formulating a propagation velocity model for 3D mapping of the dielectric constant of the medium, within macro and micro scale of the rock mass of a bench in a sandstone quarry. This finding is significant for future improvement of the deterministic accuracy level of the developed fracture modeling approach and, generally, for the GPR applications in rock mass. Regarding quarrying optimization, two 3D algorithms, based on fracture modeling or mapping, were developed for production and/or revenue optimization of cutting slabs from blocks and cutting blocks from benches. The algorithms were coded in two software packages named SlabCutOpt and BlockCutOpt. SlabCutOpt was applied to a case study of a limestone block through testing 37 different commercial-sizes of slabs, investigating the optimization results in terms of recovery ratio (a geo-environmental direction) and revenue (an economic direction). BlockCutOpt was applied to two case studies (quarries) with different site characteristics. The results showed that optimum cutting direction of blocks can vertically and horizontally vary, giving geometric information about the cutting grid of blocks that optimizes the production.

The document is an extended abstract presented at "GeoENV 2016", the 11th International Conference on Geostatistics for Environmental Application Conference, 6-8 July 2016, Lisbon, Portugal.

The document is an extended abstract presented at "GeoENV 2016", the 11th International Conference on Geostatistics for Environmental Application Conference, 6-8 July 2016, Lisbon, Portugal.

Površinske temperature i hidrogeološki uvjeti ključni su parametri u mnogim inženjerskim primjenama poput izgradnje podruma i drugih podzemnih prostorija te kod procjene plitkoga geotermalnog potencijala. Međutim, teško je otkriti prirodne, tj. izvorne, toplinske uvjete, poglavito u plitkim, podzemnim, gradskim područjima. Razlog tomu je ljudski utjecaj. Stoga procjena toplinskih varijabli u takvim uvjetima postaje sve važnija, jer raste i uporaba geotermalne energije, posebice kao obnovljivoga izvora. Cilj rada bio je prikazati trodimenzionalni model takvih uvjeta, kalibriran eksperimen-talnim podatcima. Tako je opisano ponašanje topline u podzemlju pod utjecajem građevina u odabranome seoskom području Italije. Temperaturne varijacije u prostoru i vremenu ovisile su o površinskim stijenama (i/ili tlu), klimi i svojstvima same građevine. Svi ti parametri razmatrani su unutar modela sezonskih promjena temperatura. Rezultati modela u područjima niske urbanizacije neizravno upućuju kako promatrani parametri imaju veliku važnost u visoko urbaniziranim područjima. Nadalje takvi rezultati mogu se uključiti u buduće modele plitkoga podzemlja i razmjenji-vača topline te unaprijediti kako njih, tako i opću uporabu geotermalne energije. Ground temperature and hydrogeological conditions are key parameters for many engineering applications, such as the design of building basements and underground spaces and the assessment of shallow geothermal energy potential. Especially in urban areas, in the very shallow depths, it is difficult to find natural undisturbed underground thermal conditions because of anthropic interventions. The assessment of underground behaviour in disturbed conditions will become more and more relevant because of increasing awareness to energy efficiency and renewable energy topics. The purpose of this paper is to show a three-dimensional representation - based on models calibrated on experimental data - of the underground thermal behaviour affected by a building in a rural area in Italy. Temperature varies in space and time and it depends on ground, climate and building characteristics, and all these parameters are taken into account by the seasonal periodic modelling implemented. The results obtained in a context of low urbanization indirectly suggest the importance of these effects in dense urban areas; taking greater account of these aspects could lead to improvements in the design of underground spaces and geo-exchanger fields for geothermal energy exploitation.

The exploitation potential of shallow geothermal energy is usually defined in terms of site-specific ground thermal characteristics. While true, this assumption limits the complexity of the analysis, since feasibility studies involve many other components that must be taken into account when calculating the effective market viability of a geothermal technology or the economic value of a shallow geothermal project. In addition, the results of a feasibility study are not simply the sum of the various factors since some components may be conflicting while others will be of a qualitative nature only. Different approaches are therefore needed to evaluate the suitability of an area for shallow geothermal installation. This paper introduces a new GIS platform-based multicriteria decision analysis method aimed at comparing as many different shallow geothermal relevant factors as possible. Using the Analytic Hierarchic Process Tool, a geolocalized Suitability Index was obtained for a specific technological case: the integrated technologies developed within the GEOTeCH Project. A suitability map for the technologies in question was drawn up for Europe.