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Abstract The bigger mine waste dumps create the greater the issue to encounter in situ ground conditions. Landfill rock waste makes an inadequate strength and economic issue of the reclamation work is more difficult, especially in determination of slope stability. A clear differentiation based on the lump-size rock type and soil distribution and compression in the field of reclamation. GEO5 FEM, Rocklab and Stereonet7 programs performed with four rockfill modeling and stability analysis for A1, A2, A3 and A4 rock fills models where rock fills of the dump slope were limited. Anisotropic rockfill and soil mixture models were made in laboratory scale. Heterogeneous geotechnical parameters were analyzed. Regarding the topographic maps produced in the 1/1000 scale with field work and the structural cross sections of rock fill models conducted on laboratory experiments, the physical and mechanical properties for each A1, A2, A3 and A4 Models. A1, A2 slopes were close to stable state that showed to be slight safety risk. However, GEO5 programs with limestone fill model through FEM program exhibited stability with A3 and A4. 1 Introduction Because of growing urbanization, reclamation of mine waste dumps is required and has to be concerned. New and bigger urbanization area may face to the reclamation issue around the civil structures. The geotechnical parameters of ground are the decisive factor regarding the type of slope stability work and its efficiency (Bieniawski 1967, Cernica 1995, Das 1994). In the stable ground, the slope has to be actively supported in order to avoid ground settlement. Modified impact resistance of rocks makes use of the 20โ30 cm lump massive rock model to provide face scale to 2โ3 cm. The indentation by the drilling bit enters in-situ the massive lump rock, where the volume of rock retained can regulate through the advance rate. Depending on the resistivity of the rock volume in the dump, the indentation pressure can be controlled. The pressure can be calculated depending on the slope (bit diameter, overburden depth), geological and hydrogeological conditions and any surcharge in the area affecting the stability alignment (Gรถrรถg & Tรถrรถk 2006, Gรถrรถg & Tรถrรถk 2007). The calculation of slope stability of mixed face conditions of the varied rockfills such as local porous limestone, marly limestone. The waste shale and marly shale is based on the assumption of a linear (hydrostatic) distribution of support pressure over the face, which is in equilibrium with the scaling ground and water pressures in laboratory model (Bishop 1955, Hoek 1970, Hoek 2013, Hoek & Brad 1977). However, evaluation of data is made by GEO5 FEM model program (Anonymous 2009, Anonymous 2009, Pruska 2009). Earth face in-situ measurement systems have demonstrated dynamic non-linear stress distribution with strong fluctuations at times of high tonnage lorries transfer. This showed in particular differences between the phones at the slope face and critical weakness spaces in the dumps.
- Europe (0.69)
- Asia > Middle East > Turkey (0.48)
- North America > United States (0.29)
- Geology > Rock Type > Sedimentary Rock > Carbonate Rock > Limestone (0.68)
- Geology > Rock Type > Sedimentary Rock > Organic-Rich Rock > Coal (0.50)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock > Shale (0.48)
- Water & Waste Management > Solid Waste Management (0.91)
- Energy > Oil & Gas > Upstream (0.89)
- Materials > Metals & Mining (0.83)
Abstract In this note, results of triaxial laboratory tests on very weak sedimentary limestone from the construction of the "Geusselt A2" tunnel in Maastricht in the Netherlands are presented. The main purpose of the triaxial tests was to evaluate the strength of this rock. Particularly interesting was that the strength parameters obtained in the laboratory, were much lower than what was expected after preliminary visual inspections. The two most popular models in soil and rock mechanics, the Mohr-Coulomb and Hoek-Brown failure criteria, were used to estimate the strength parameters and both did not give satisfying results. Still the Mohr-Coulomb model is the best model to use. 1 Introduction The highway A2 crosses the middle of the city of Maastricht in the south Netherlands. This is why a shallow tunnel is constructed here. For purposes of the building pit's design, the strength of the local rock, which is part of the Maastricht Formation, had to be properly determined. Therefore, triaxial laboratory tests on this soft rock were conducted. The Maastricht Formation is a geological formation in the Dutch Limburg province, Belgian Limburg and adjacent areas in Germany. The rock belonging to Maastricht Formation, locally known as "mergel", is an extremely weak, porous rock consisting of soft, sandy, shallow marine, weathered carboniferous limestone, well as chalk and calcarenite. The tests were conducted on a very young and shallow rock layer, so the material was not much compacted and cemented. It was therefore expected that the strength parameters will be low. To obtain the samples for laboratory tests, a visitation and sampling on site at the building pit Geusselt A2-Maastricht was done by the University of Luxembourg, with the help of E. van Herk and B. Vink from the contracting combination Avenue2 (Strukton and Ballast Nedam). Figure 1 presents the site from where the rock samples were obtained on 5 September 2013.
- Europe > Netherlands > Limburg > Maastricht (1.00)
- Europe > Norway > Norwegian Sea (0.24)
- Geology > Rock Type > Sedimentary Rock > Carbonate Rock > Limestone (0.97)
- Geology > Geological Subdiscipline > Geomechanics (0.67)
- Health & Medicine > Diagnostic Medicine > Lab Test (1.00)
- Energy > Oil & Gas > Upstream (0.70)
Abstract Selection of support system is important for safety concerns and economic aspects. The purpose of this study is to investigate the design of support system specific to an underground mine in Balya, Balikesir, Turkey. The mine has been operated by Eczacibasi Group Esan Company since 2009 for lead and zinc production. Support systems were designed by using rock mass classification systems based on the data regarding underground openings, rock mass and support materials. The suitability of the designs were evaluated by using numerical methods to understand the effect of support materials by considering the difference between total displacement and strength factor both for supported and unsupported conditions. The effect of existing underground openings that are adjacent galleries were also simulated in the numerical models that could not be modelled in rock mass classification systems. The studies were completed a design procedure for a similar underground mines successfully. 1 Introduction Design of support systems is an important part of planning as well as site applications for a sustainable ore production. The studies are mostly carried out by considering in situ stress, stress around the openings, evaluation of rock burst, and squeezing conditions. Rock Mass Rating (RMR) proposed by Bieniawski (1989) and Q-system (Barton et al. 1974) classifications are employed as empirical methods to select support systems for underground openings. The results obtained from these studies can be combined to design underground opening's support system. These empirical methods similar with the analytical solutions mostly ignore the effect of existing underground openings. In order to obtain proper and optimized solutions during support design studies, some other methods such as numerical methods should be applied to understand the effect of other important features around underground openings. Underground mining with its complicated underground structures requires different solutions for support design problems due to its complicated and intricate structural relations based on underground mine production method. A lead and zinc underground mine is selected as a case study area that is operated by Eczacibasi Group Esan Company since 2009. The mine is located in Balya Balikesir, Turkey (Figure 1). A mineral processing plant with a daily capacity of 4,250 ton raw ore material has been also operating as a part of the mine. Production of the underground mine is sternly 4,250 ton per day, and the mine reaches 745 m depth for present. The mine is one of the important underground metalliferous mine in terms of its capacity, depth, and daily production rate in Turkey. Sublevel cut and fill stoping underground mining method has been applied for the production of ore. The ore is produced from sublevel production galleries where levels are constructed in every 15 m height. The open stopes are filled by cemented backfill material for the excavation of adjacent production galleries as well as forming working platforms for upper sublevel. The size of the production galleries are in rectangular shape with 25 m area while the size increases up to 36 m area since the mine goes down deeper. Fibrecrete, rock bolts, and wire mesh are the main support materials and engineering properties of these materials were also determined in order to simulate the suitability of support materials for underground openings.