Optimal Design of Waste-Dump Slope of Open Pit Mine Based on Strength Reduction FEM

The dumps in the open-pit mining area in the eastern grassland are prone to landslides due to the fragile ecological environment, so it is inevitable to reshape the dump slopes. In order to explore a more scientific method for slope shaping of open-pit mine dump, slope stability analysis were used to compare effect of three types of slope-type (wave-shaped, slope-shaped and step-shaped slope shaping method)in outside dumping site of Baori Hiller open-pit mine. The results show that the slope stability is negatively correlated with the slope angle, and the stability of different shaping slopes is realized as wave-shaped slope (F=2.711)> Slope-shaped slope(F=2.513)>Step-shaped slope(F=1.047), in which the wave type and slope type are all within the safe range, but the step type slope is unstable; in consideration of cost, stability and erosion resistance, it is better to set the slope angle of the dump to 15°.The wave-shaped shaping method of the natural dumping of the excavation field outside the Baori Hiller open-pit mine has the best effect and is worth promoting.

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Stability Analysis of Dump Slope Based on FEM Strength Reduction Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.501-504.51 ◽

2014 ◽

Vol 501-504 ◽

pp. 51-55 ◽

Cited By ~ 2

Author(s):

Chao Peng ◽

Dong Ji ◽

Liang Zhao ◽

Zhen Yu Qian ◽

Fen Hua Ren

Keyword(s):

Safety Factor ◽

Reduction Method ◽

Strength Reduction ◽

Production Costs ◽

Open Pit ◽

Strength Reduction Method ◽

Reduction Algorithm ◽

Safety Factors ◽

Dump Slope ◽

The Stability

An analysis on safety factor of slope through c - φ reduction algorithm by finite elements method is presented. When the system reaches instability, the numerical non-convergence occurs simultaneously. The safety factor is then obtained by c φ reduction algorithm. This paper, which combines with the actual situation of Jinduicheng open pit mine, analysis the stability of the limit height of the dump based on strength reduction of finite element method. And the value of slope safety factor is 1.25 to 1.30. The results show that calculating safety factors of the slope by ANSYS is in full conformity with the basic requirement of safety. That means, the dump is stable, which can reduce the production costs and benefit the enterprise.

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Start-Up Mechanism and Dynamic Process of Landslides in the Full High Waste Dump

Water ◽

10.3390/w12092543 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2543

Author(s):

Chunhui Cao ◽

Jili Feng ◽

Zhigang Tao

Keyword(s):

Dynamic Process ◽

Shear Failure ◽

Numerical Technique ◽

Field Investigation ◽

Open Pit Mine ◽

Open Pit ◽

Waste Dump ◽

Thaw Cycle ◽

Shape Influence ◽

Map Data

Landslides often occur in the open-pit mine dump, which is harmful to the safety operation of mines and slopes. In this work, the landslides that occurred in 2014 at Nanfen open-pit mine of China are studied to understand the triggering mechanism and dynamic process of landslides in the full high waste dump. Field investigation, hydrogeological data analysis, satellite map data, and numerical simulation are combined to analyze and evaluate the landslides. The study shows that the continuous and intensive dumping can lead to shear failure under the action of self-weight. The shear strength of loose dump bodies significantly relies on the water content, freeze-thaw cycle, pore pressure, and gradation of the dump soils. These factors result in the occurrence of landslides in the dump slope. The predictions by the smoothed particle hydrodynamics method show that the shape, influence range, and slip distance of landslides are consistent with that of the field investigation. The present study shows that the SPH method is a powerful numerical technique to describe landslides’ problems.

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Study on the Influence of Rainfall Infiltration on the High rock Slope of Open-pit Mine Stability using a New Nonlinear Strength Reduction Method

10.21203/rs.3.rs-914757/v1 ◽

2021 ◽

Author(s):

Tianbai Zhou ◽

Lingfan Zhang ◽

Jian Cheng ◽

Jianming Wang ◽

Xiaoyu Zhang ◽

...

Keyword(s):

Rock Mass ◽

Rock Slope ◽

Reduction Method ◽

Strength Reduction ◽

Open Pit Mine ◽

Open Pit ◽

Strength Reduction Method ◽

Rock Slopes ◽

High Rock Slope ◽

The Stability

Abstract Due to long-term mining, a series of high and steep rock slopes have been formed in the open-pit mine. For high rock slopes, rainfall infiltration is the main cause of landslide. Therefore, the stability analysis of high rock slope under rainfall has become a key issue in the open-pit mine engineering. In this work, aiming at the high stress condition of high rock slope, the instantaneous internal friction angle and instantaneous cohesion of rock mass under different stress states are deduced, and the a nonlinear strength reduction method for high rock slope is established according to the relationship between normal stress and shear stress of rock mass under the Hoke-Brown criterion. The numerical calculation results show that the factor of safety (FOS) for high rock slope calculated by the proposed method is more reasonable. Taking the southwest slope of Dagushan Iron Mine as the research background, the safety factors of high rock slope under different rainfall conditions are calculated by COMSOL Multiphysics. And the stability analysis of high rock slope in open-pit mine under rainfall are carried out.

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The 2D and 3D Stability Analysis of Spreader for Open-Pit Iron Mine

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.813.263 ◽

2013 ◽

Vol 813 ◽

pp. 263-268 ◽

Cited By ~ 1

Author(s):

Xiao Lei Qian ◽

Yun Peng Ren ◽

Su He Gao ◽

Guo Qiang Wang

Keyword(s):

Genetic Algorithm ◽

Finite Element ◽

Safety Factor ◽

Limit Equilibrium ◽

Strength Reduction ◽

Open Pit ◽

Normal Operation ◽

Simple Genetic Algorithm ◽

Dump Slope ◽

2D And 3D

To determine the safe distance between spreader and the upper verge of dump slope, a 2D and 3D slope model was built respectively, the limit equilibrium method and the finite element method with shear strength reduction technique (FEM-SSR) were introduced to analyze the stability of the spreader. For the slope under the action of variable external loads, the simple genetic algorithm (SGA) sometimes fails to converge to the global optimum, for this reason, an improved optimum maintaining simple genetic algorithm (OMSGA) was utilized to search for the critical slip surface, and the probability of the global convergence was improved greatly. On the basis of the three-dimensional elastic-plastic finite element model of the dump slope, the minimum sinkage of spreader track which interferes the spreaders normal operation was taken as the criterion to determine the safety factor, according to this idea, the deformation in the elastic stage during the process of strength reduction was considered, and a more reliable safety factor by the variable stiffness method was obtained.

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Variation of Open-Pit Waste Dump Specimens Under Effective Pressure Influence

Frontiers in Earth Science ◽

10.3389/feart.2020.582918 ◽

2021 ◽

Vol 8 ◽

Author(s):

Gerson. S. V. Tovele ◽

Liu Han ◽

Ji Sen Shu

Keyword(s):

Void Ratio ◽

Open Pit ◽

Effective Pressure ◽

Waste Dump ◽

Overburden Pressure ◽

Preventative Measures ◽

Coefficient Of Permeability ◽

Dump Slope ◽

Physical Changes ◽

And Control

The waste dump is a giant artificial loose pile body composed of fine, medium, and coarse particle sizes. Rising incidents of landslides caused by overburden pressure and effective pressure are of increasing concern in the open-pit waste dump and, if not well-controlled, are a dangerous threat to the workers, the environment, and the equipment. The purpose of this research is to investigate the connection between effective pressure, porosity, void ratio, and coefficient of permeability and to find their influence in the open-pit waste dump. This study analyzed the mechanical and physical changes of seven different soil samples using consolidation and permeability under consolidation laboratory test. The test samples were subject to a pressure ranging from 100 to 1600 kPa. The effective pressure was found to play a major role in influencing void ratio, porosity, and coefficient of permeability, and waste dump height management and control are of great importance. This study answers the question regarding the correlation between effective pressure, void ratio, porosity, and coefficient of permeability in the open-pit waste dump. Further studies are needed to establish profound relationships and develop preventative measures to keep the waste dump slope stable and safe.

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Stability Analysis of Slope with Multiple Sliding Surfaces Based on Dynamic Strength-Reduction DDA Method

Advances in Civil Engineering ◽

10.1155/2019/2183732 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12

Author(s):

Shuhong Wang ◽

Chengjin Zhu ◽

Pengyu Wang ◽

Zishan Zhang

Keyword(s):

Stability Analysis ◽

Slip Surface ◽

Dynamic Strength ◽

Strength Reduction ◽

Open Pit Mine ◽

Discontinuous Deformation Analysis ◽

Open Pit ◽

Sliding Surfaces ◽

Displacement Threshold ◽

Dda Method

The present study aims to elucidate the problem of a rock mass structural plane with a range of damage degrees and the numerical model selection for analysis of a slope with multiple sliding surfaces. Based on the relative displacement between blocks, the dynamic strength reduction-discontinuous deformation analysis (hereinafter referred to as DSR-DDA) method is proposed for studying slopes with multiple sliding surfaces. The slope-slider classic case was used to test the displacement threshold. The model was applied to the stability analysis of multiple sliding surfaces of a high rock slope in the Fushun West Open-Pit Mine. The results show that when the displacement threshold is set to 1 mm, the error between the DSR-DDA results and the theoretical solution is within 0.5%, which satisfies the calculation requirements. The most dangerous slip surface in the Fushun West Open-Pit Mine slope was identified. Based on the numerical slope model after the first landslide, the position of the secondary slip surface was then identified. The failure mode is traction sliding failure, and the middle and lower oil shales play a key role in the slope stability. This study recommends that mining of the remaining oil shale should stop to avoid causing large-scale landslides in the upper part of the slope and landslides at the pit-city boundary.

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