Environment
Ayodele Owolabi; Sunday DARAMOLA
Abstract
Nigeria is abundantly blessed with solid mineral resources such as copper, gold, and tantalite, which are essential for the economic growth of the country. The extraction of these mineral resources comes with the generation of huge amount of waste. This study examines the possibility of utilizing some ...
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Nigeria is abundantly blessed with solid mineral resources such as copper, gold, and tantalite, which are essential for the economic growth of the country. The extraction of these mineral resources comes with the generation of huge amount of waste. This study examines the possibility of utilizing some mine wastes from Jos, Nigeria, in embankment construction by subjecting them to relevant laboratory geotechnical experiments. The results indicates that the overburden materials contain clay-sized fraction ranging 5-20%, while the sand fraction ranged 42-82%, which is an indication of the predominance of sand size particles. On the other hand, the clay-sized particles in the tailings range 5-21%, while the sand fractions range 65-80%. The overburden materials recorded liquid limit values ranging 26-48% and plasticity index ranging 6.3-21%, while the liquid limit and plasticity index of the tailings range 23-32.8% and 6.2-11.6%, respectively. The maximum dry density (MDD) and optimum moisture content (OMC) of the overburden materials vary 1.84-1.98 mg/m3 and 1.4-17.2%, respectively, with an average of 1.89 mg/cm3 and 16%. On the other hand, the tailings recorded MDD ranging 1.88-2.06 mg/m3 with their OMC ranging 14.4-16% with an average 14.86%. The soaked California bearing ratio (CBR) of the overburden materials range 27-32%, while that of tailings ranges 25-32%. The geotechnical evaluation of the overburden materials and tailings reveals that most of the materials are suitable for embankment construction. However, the high linear shrinkage of some wastes renders them unsuitable.
Environment
Akbar Esmaeilzadeh; Korosh Shahriar; Reza Mikaeil
Abstract
The hydraulic properties of the rock masses are of great importance in analyzing the behavior and stability of the structures constructed on or in rock mass. Permeability is key parameter among other rock mass features due to its important role in rock mass overall behavior. According to aforementioned ...
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The hydraulic properties of the rock masses are of great importance in analyzing the behavior and stability of the structures constructed on or in rock mass. Permeability is key parameter among other rock mass features due to its important role in rock mass overall behavior. According to aforementioned reason, numerous efforts have been made by researchers in the field of rock mechanics for its obtaining. To access the rock masses’ permeability, in-situ test methods and simulation techniques could be used. In-situ tests like Lugeon Test are time-consuming and costly and they provide local results. Simulation base methods calculate the permeability of the model that is generated similar to the real region indeed and the developing the results to the real condition always raises substantial challenges. according to the aforementioned reason, direct acquiring of permeability with optimum cost and time which is easily generalizable to the overall of a region would be very important. In this work using crack tensor concept, permeability tensor of Lorestan’s Rudbar dam cavern is calculated efficiently by considering rock mass structural features. Resulted permeability of the power plant’s cavern was obtained equal to that seems to be acceptable compared to the measured values which is obtained 9/87×10-7 m/s.
