Rock Mechanics
Mostafa Rahimiyan; Mohammad Ataei; Reza Kakaie; Hossein Khosravi
Abstract
The identification of rock discontinuities is a critical factor in the field of mining and construction projects. Traditional methods for conducting this task is often difficult, time-consuming, poses risks to the human safety, and lead to incomplete evaluations. With introduction of unmanned aerial ...
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The identification of rock discontinuities is a critical factor in the field of mining and construction projects. Traditional methods for conducting this task is often difficult, time-consuming, poses risks to the human safety, and lead to incomplete evaluations. With introduction of unmanned aerial vehicles (UAV) has changed this process and has allowed to cover all the area in a short time without endangering employees. The aim of this paper is to employ deep learning using python programming language to develop and train a neural network based on the UNET++ architecture in order to identify rock surface discontinuities automatically by means of UAV-captured imagery. It is also addresses challenges associated with supervised learning, particularly overfitting, by implementing data augmentation techniques and reducing model parameters by approximately 6%. Consequently, the pixel-wise precision criterion improved significantly from 53.27% to 75.6%. Especially, this work stands out from other studies by focusing specifically on UAV imagery for geological assessments, employing a dual strategy to overcome overfitting, and demonstrating effective performance despite the limited training data. The result showed that the model is capable to identify rock discontinuities accurately and is a suitable method for the mining and construction industries.
Rock Mechanics
H. Zebarjadi Dana; R. Khaloo Kakaie; R. Rafiee; A.R. Yarahmadi Bafghi
Abstract
Slope stability analysis is one of the most important problems in mining and geotechnical engineering. Ignoring the importance of these problems can lead to significant losses. Selecting an appropriate method to analyze the slope stability requires a proper understanding of how different factors influence ...
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Slope stability analysis is one of the most important problems in mining and geotechnical engineering. Ignoring the importance of these problems can lead to significant losses. Selecting an appropriate method to analyze the slope stability requires a proper understanding of how different factors influence the outputs of the analyses. This paper evaluates the effects of considering the real geometry, changes in the mesh size, and steepness of the slope, as the dimensional effects, and changes in the geomechanical parameters, as the media effects on the global slope stability of an open-pit mine using finite difference methods with a strength reduction technique. The case study is the Tectonic Block I in the old pit (steep slope) and the redesigned new pit (gentle slope) of the Choghart iron mine. In the first step, a series of 2D and 3D slope stability analyses are performed and compared in terms of safety and potential failure surface. The results obtained show that by considering the real geometry of the slope, the FOS3D/FOS2D ratio (3D-effect) is more than 1 in the all cases. The 3D-effect in the new pit is smaller than that in the old one. In the next step, sensitivity analysis of the cohesion and the friction angle is performed for the 2D and 3D analyses. The results obtained show that the sensitivity of the analyses in terms of the 3D-effect to the change in the friction angle, especially in a low-friction angle, is more significant than that to the change in the cohesion.
ebrahim elahi; Reza Kakaie; amir yusefi
Abstract
Ultimate limits of an open pit, which define its size and shape at the end of the mine’s life, is the pit with the highest profit value. A number of algorithms such as floating or moving cone method, floating cone method II and the corrected forms of this method, the Korobov algorithm and the corrected ...
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Ultimate limits of an open pit, which define its size and shape at the end of the mine’s life, is the pit with the highest profit value. A number of algorithms such as floating or moving cone method, floating cone method II and the corrected forms of this method, the Korobov algorithm and the corrected form of this method, dynamic programming and the Lerchs and Grossmann algorithm based on graph theory have been developed to find out the optimum final pit limits. Each of these methods has special advantages and disadvantages. Among these methods, the floating cone method is the simplest and fastest technique to determine optimum ultimate pit limits to which variable slope angle can be easily applied. In contrast, this method fails to find out optimum final pit limits for all the cases. Therefore, other techniques such as floating cone method II and the corrected forms of this method have been developed to overcome this shortcoming. Nevertheless, these methods are not always able to yield the true optimum pit. To overcome this problem, in this paper a new algorithm called floating cone method III has been introduced to determine optimum ultimate pit limits. The results show that this method is able to produce good outcome.
