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The mechanical behavior of rock salt has been studied for many decades. Early engineering studies were driven largely by the need to design safe salt mines. In recent times more of the study is concerned to understand the long term behavior of the rock salt to develop and assess the safety of rock salt deposits for the storage of radio active waste. The physical and mechanical characteristics of salt are evidenced in its compact texture, low porosity, low permeability and strong rheological properties (creep behavior). These properties are however necessary for stability analysis and the design of engineering structures in salt mines. Long term effect of the temperature on rock salt mechanical behavior has been documented by various researchers. Temperature also has pronounced effect on short term behavior like instant strength of the rock salt. Generally the trend is that as the temperature increases the instant strength decreases. For the stability of structures like solution-mined caverns, dry salt mines, storage and disposal caverns and boreholes used in the exploration and production of oil and gas comprehensive study of the instant strength of the rock salt is also vital. The objective of this research was to study the temperature effect on the instant strength of the rock salt obtained from Polkowice - Sieroszowice mine in the Lower Selicia. After laboratory tests using uniaxial compressive strength test method, it was observed that the at the given range of temperature applied in the test (10 degree C to 80 degree C) the rock salt instant strength does not show any correlation with the temperature. In other words the instant strength of the rock does not decrease as temperature increase. This kind of unanticipated behavior towards the temperature in terms of strength which is rare for the rock salt could be due to the reason that the range of temperature used in the test was not sufficient for the rock salt to show any alteration in its strength value. Since there was no significant effect of given temperature range on the strength values of the rock salt, classical failure criterion like Mohr-Coulomb criterion was considered as the suitable criterion to justify the strength changes on the rock salt samples. On the other hand density emerges out as a crucial factor that influences the instant strength of the rock salt. Higher uniaxial compressive strength values can be observed for the samples having higher density. This research work is useful to understand the mechanical behavior of the rock salt which behaves in a complex manner when there are lots of factors involved like geology, temperature, density, loading history, maturity of the crystals etc. are involved. It is therefore deemed necessary that more through studying and testing is required.

Roads support our daily life, and play crucial role in supporting the infrastructure for economic activities. However, road disaster can be caused by different natural conditions of slope failures such as rainfall, steep topography, brittle geology, etc. Road disaster occurrences do not only cause the primary disaster from the infrastructure point of view; but also the secondary disaster, hindrance to the society and the economic activity by traffic stops. In order to prevent or mitigate such road disasters caused by diverse reasons; measures should be taken in every phases of road engineering practices, usually mainly thorough investigation about the surface geology, the subsurface conditions of the foundation and the careful testing of the construction materials principally. Hence detailed investigation about the site is compulsory before commencing the design and construction phases. In addition, post construction phases mainly regular monitoring and maintenance must be undertaken to give the intended service of the highway. Limit equilibrium method is one of the most widely used stability analysis in practice due to its reliability for most practical cases. Its simplified approach can be used in the preliminary assessment only while more complex analysis that gives more accurate results can be carried out with computer programs. This research presents results of stability analysis of A-8 motorway Wroclaw bypass on selected embankments under construction founded on heterogeneous soft soil layers. Different methods of limit equilibrium analysis adopted in computer analysis program SLIDE 2D was used to calculate the Factor of Safety of each embankment. The discussion was based on the results of the computation carried out for cross-sections of A-8 motorway characterized by variability of height and reinforcement conditions. The limit equilibrium method which satisfies both force and moment equilibrium give better prediction on the stability of the slope. In addition to that the method whose assumption mimics the slope condition is preferred. The assessment was executed by referring to the slope stability requirement by Polish regulations.

This thesis studies the zinc extraction from spinels through hydro and pyrometallurgical processing. Two zinc-bearing spinels are covered: zinc ferrite ZnO·Fe2O3 to a limited extent and gahnite ZnO·Al2O3 as the main subject, compounds which are found naturally on the Earth’s crust as well as in industrial residues from the zinc industry, steel industry and others. Zinc ferrite contains 27 % of Zn and 33 % as ZnO; resource recovery from ferrite has been studied already in the past. On the other hand, the processing of gahnite, containing 35 % of Zn and 44 % as ZnO, is studied more extensively since research in the field of extractive metallurgy is effectively non-existent. Hence, the main objective of the present thesis is finding routes of treatment for this spinel. Zinc ferrite was produced synthetically at the CiTG/3mE labs by mixing equimolar amounts of ZnO and Fe2O3 at 1100 °C. Gahnite was produced by an analog method, a mixture of equimolar amounts of ZnO and Al2O3. The first approach was hydrometallurgical. Atmospheric hot acid leaching (4 M, 95 °C, 120 min, L/S 40) was performed with H2SO4, HCl and HNO3, resulting in a non-detected dissolution of the compound. Pressure leaching (90 min, L/S 40) was carried out in an autoclave with H2SO4 and HNO3, resulting in a low (2.9 %; 0.75 M, 140 °C, 3.6 bar) and a moderate extraction (22.2 %; 4.0 M, 250 °C, 39.7 bar) respectively. The second approach was pyrometallurgical processing (60 min dwell, 10 °C/min heating rate), divided into two sub-routes. A series of carbothermic tests (1:1.25 stoichiometric ratio) successfully led to a full reduction of the spinel at 1300 °C (99.90 % extraction of zinc). Aluminothermic tests (1.5:2 stoichiometric ratio) successfully resulted in a 99.98 % zinc extraction at 1200 °C. The mix of gahnite and ferrite with carbon at 1300 °C produced a 99.65 % extraction of the metal. Addition of ZnO to the previous mixture resulted in a 100 % extraction, at 1300 °C. Further experiments with gahnite at 1200 °C by adding SiO2, first with carbon and later with aluminium, resulted in a moderate 23.14 % and a low 4.69 % extraction correspondingly. Trials with CaO at 1400 °C created a glass residue and a slag, in each case. It is thus possible to establish the zinc extraction from gahnite ZnO·Al2O3 as follows: Route / Zinc extraction Atmospheric acidic leaching / Non-detected Pressure leaching / Low – Moderate Reduction with aluminium and silica / Low Reduction with carbon and silica / Moderate Carbothermic reduction / Full Aluminothermic reduction / Full

This thesis describes and substantiates the design and development of CaveCad, a state of the art integrated cave management system. CaveCad is Rio Tinto proprietary software. The scope of this project is to design, develop and implement an integrated cave management system for Rio Tinto Underground Technology Centre. A successful outcome will result in the implementation of CaveCad on all Rio Tinto caving operations. The block caving mining method is being increasingly applied as a mass mining method used to exploit base metals and diamond resources. In block cave mining, geotechnical monitoring is fundamental to the successful management and operation of the mine. Current state of the art in monitoring, although innovative and useful, has lacked the collective integration of multiple systems from which collective information can be used to make unambiguous and timely decisions. This is the reason for the design, development and subsequent application of CaveCad. In addition to the design and development process of CaveCad, this study includes background information on block caving and cave monitoring, data research on the relevant monitored data types and a comprehensive case study. It also includes software research into the different system components and the testing of the Geotech module, a GOCAD Mining Suite geotechnical plug-in. Finally, the first CaveCad module, which was released in December 2011, is fully described. The report concludes with a discussion, recommendations and a conclusion. The database and system architecture comprising CaveCad has been successfully designed and developed. However, this thesis does not include the implementation phase as the first released version lacked essential functionality. The estimated release and site implementation date of the updated CaveCad module is March 2012.