A holistic approach to open-pit slope stability using Artificial Neural Networks and Rock Engineering Systems Approach
- Authors: Fakir, Muhammad
- Date: 2018
- Subjects: Strip mining - Planning , Slopes (Soil mechanics) , Rock mechanics , Soil stabilization , Earth construction
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/280443 , uj:30135
- Description: M.Phil. (Civil Engineering) , Abstract: As open-pit mines become deeper, the stability aspects of large slopes can be at the limit or beyond precedent practice. There are new design demands, scale related challenges, continuous blasting effect to the rock mass, various complex interactions between rock stress, fractures, and water flow, over long periods. Thus, there is a greater probability of slope failure associated with deeper and eventually steeper slope development. Interactions between the factors affecting slope stability in open-pit mines are therefore more complex and often difficult to define. Determination of the non-linear behaviour of such a multivariate dynamic system is often challenging and demanding. In addition, the problem is often dictated by non-linear equations. Therefore, there is a need for the proposal of an intelligent slope stability index. A new objective holistic approach is proposed in order to address the status of stability of slopes in open-pit mines. Through this approach the primary role of rock mass structure, in situ stress, waterflow, and construction effect have been extended into 18 system parameters describing the overall environment, intact rock quality, rock mass properties, in situ rock stress, hydraulic conditions, discontinuities properties, geometry, construction, and history of instabilities. Soft computing methods such as Back Propagation, Self-Organising Maps, and Artificial Neuro Fuzzy Inference System algorithms are used in conjunction with the Rock Engineering Systems approach to assess the stability status of 141 open-pit slopes in a complex rock engineering system. Implementation of the Rock Engineering System allows for the complex interaction investigation between the influential parameters using the generic interaction matrix. The central reasoning behind employing ANN to slope stability in open-pit mines is its ability to identify interesting and useful patterns in data. Hence, new knowledge is gained with regards to the open-pit engineering environment in an attempt to reduce the associate uncertainty. An Intelligent Open-pit Mine Slope Stability Index is proposed to assess the potential status regime from an objective holistic point of view. The reliability of the predictive capability is computed as the Mean Squared Error, and further validated through a Receiver Operating Characteristic curve. Together with the Mean Squared Error, and Receiver Operating Characteristic curve of 92%, 97% and 98% for Back Propagation, Self-Organising Map, and Artificial Neuro Fuzzy Inference System respectively, the application illustrates that the prediction of slope stability through Artificial Neural Networks produces fast convergence giving reliable predictions, and thus being a useful tool at the preliminary stage of open-pit slope stability project.
- Full Text:
- Authors: Fakir, Muhammad
- Date: 2018
- Subjects: Strip mining - Planning , Slopes (Soil mechanics) , Rock mechanics , Soil stabilization , Earth construction
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/280443 , uj:30135
- Description: M.Phil. (Civil Engineering) , Abstract: As open-pit mines become deeper, the stability aspects of large slopes can be at the limit or beyond precedent practice. There are new design demands, scale related challenges, continuous blasting effect to the rock mass, various complex interactions between rock stress, fractures, and water flow, over long periods. Thus, there is a greater probability of slope failure associated with deeper and eventually steeper slope development. Interactions between the factors affecting slope stability in open-pit mines are therefore more complex and often difficult to define. Determination of the non-linear behaviour of such a multivariate dynamic system is often challenging and demanding. In addition, the problem is often dictated by non-linear equations. Therefore, there is a need for the proposal of an intelligent slope stability index. A new objective holistic approach is proposed in order to address the status of stability of slopes in open-pit mines. Through this approach the primary role of rock mass structure, in situ stress, waterflow, and construction effect have been extended into 18 system parameters describing the overall environment, intact rock quality, rock mass properties, in situ rock stress, hydraulic conditions, discontinuities properties, geometry, construction, and history of instabilities. Soft computing methods such as Back Propagation, Self-Organising Maps, and Artificial Neuro Fuzzy Inference System algorithms are used in conjunction with the Rock Engineering Systems approach to assess the stability status of 141 open-pit slopes in a complex rock engineering system. Implementation of the Rock Engineering System allows for the complex interaction investigation between the influential parameters using the generic interaction matrix. The central reasoning behind employing ANN to slope stability in open-pit mines is its ability to identify interesting and useful patterns in data. Hence, new knowledge is gained with regards to the open-pit engineering environment in an attempt to reduce the associate uncertainty. An Intelligent Open-pit Mine Slope Stability Index is proposed to assess the potential status regime from an objective holistic point of view. The reliability of the predictive capability is computed as the Mean Squared Error, and further validated through a Receiver Operating Characteristic curve. Together with the Mean Squared Error, and Receiver Operating Characteristic curve of 92%, 97% and 98% for Back Propagation, Self-Organising Map, and Artificial Neuro Fuzzy Inference System respectively, the application illustrates that the prediction of slope stability through Artificial Neural Networks produces fast convergence giving reliable predictions, and thus being a useful tool at the preliminary stage of open-pit slope stability project.
- Full Text:
Geotechnical properties of marginal highway backfill stabilized with activated fly ash
- Authors: Aneke, Ikechukwu Frank
- Date: 2015
- Subjects: Engineering geology , Geotechnical engineering , Reliability , Soil stabilization , Fly ash
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/82735 , uj:18995
- Description: Abstract: Soil stabilized with fly ash is the most frequently used method in improvement of the geotechnical properties of soil in South Africa and it is increasingly gaining interest internationally. However, South Africa has several standards and regulations for the use of fly ash and other by products in the soil stabilization process as well as in concrete production. Activated fly ash has not been explored for stabilization of soils in South Africa. Therefore, the present study is an attempt to empirically evaluate the use of chemically activated class „F‟ fly ash obtained from Lethabo power plant in South Africa. The use of the activated fly ash could improve the geotechnical properties [including consistency limits, compaction properties, unconfined compressive strength (UCS), elasticity modulus, durability, california bearing ratio (CBR) and hydraulic conductivity]of the two different fine-grained soils tested in this study. A Red soil sample collected from Parktown, Johannesburg, South Africa was studied in two combinations; a proportion of 50% Kaolinite + 50% Red soil = Kaolinite soil and 30% Bentonite + 20% Kaolinite + 50% Red soil = Bentonite soil. Soils used in the study were built up from the red soil with different proportions to Bentonite and Kaolinite clays. One of the significant objectives of this study was to use mechanically and chemically activated class „F‟ fly ash to improve the geotechnical properties of the heavy clay content soils and to compare these properties with those of the same soils when untreated... , M.Ing. (Civil Engineering)
- Full Text:
- Authors: Aneke, Ikechukwu Frank
- Date: 2015
- Subjects: Engineering geology , Geotechnical engineering , Reliability , Soil stabilization , Fly ash
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/82735 , uj:18995
- Description: Abstract: Soil stabilized with fly ash is the most frequently used method in improvement of the geotechnical properties of soil in South Africa and it is increasingly gaining interest internationally. However, South Africa has several standards and regulations for the use of fly ash and other by products in the soil stabilization process as well as in concrete production. Activated fly ash has not been explored for stabilization of soils in South Africa. Therefore, the present study is an attempt to empirically evaluate the use of chemically activated class „F‟ fly ash obtained from Lethabo power plant in South Africa. The use of the activated fly ash could improve the geotechnical properties [including consistency limits, compaction properties, unconfined compressive strength (UCS), elasticity modulus, durability, california bearing ratio (CBR) and hydraulic conductivity]of the two different fine-grained soils tested in this study. A Red soil sample collected from Parktown, Johannesburg, South Africa was studied in two combinations; a proportion of 50% Kaolinite + 50% Red soil = Kaolinite soil and 30% Bentonite + 20% Kaolinite + 50% Red soil = Bentonite soil. Soils used in the study were built up from the red soil with different proportions to Bentonite and Kaolinite clays. One of the significant objectives of this study was to use mechanically and chemically activated class „F‟ fly ash to improve the geotechnical properties of the heavy clay content soils and to compare these properties with those of the same soils when untreated... , M.Ing. (Civil Engineering)
- Full Text:
- «
- ‹
- 1
- ›
- »