scholarly journals Extended Ultimate-Pit-Limit Methodology for Optimizing Surface-to-Underground Mining Transition in Metal Mines

2022 ◽  
Vol 2022 ◽  
pp. 1-9
Author(s):  
Si-Tong Ren ◽  
Yang Liu ◽  
Xin-Yi Yang ◽  
Ding-Gui Tong ◽  
Gao-Feng Ren
Keyword(s):  
Underground Mining ◽  
Surface Mining ◽  
Critical Issue ◽  
Practical Aspect ◽  
Open Pit ◽  
Optimization Approach ◽  
Original Design ◽  
Metal Mines ◽  
Iron Mine ◽  
Total Profit

The transition from surface mining to underground is a critical issue for metal mines. The commonly cited procedure cored by ultimate-pit-limit (UPL) methodology is restricted to maximize the profit from both surface and underground mining, due to the absence of the integration of the profit from either of them. Under the target for such maximization, this study proposes a new optimization approach, which directly relates the design of open-pit limit and underground stopes, by equalizing the marginal profit from either surface or underground mining. The variation of the crown pillar size is involved in this approach. The proposed approach is applied to the Dagushan iron mine, and results show the total profit increased from 3.79 billion CNYs (original design by conventional UPL methodology) to 4.17 billion CNYs (optimal design by the proposed approach), by 9.91%. Moreover, the marginal profit from surface and underground mining, as well as total profit, of all possible designs of surface-to-underground mining transition in Dagushan iron mine is calculated to validate the proposed approach. When the marginal profits satisfy the criterion of the proposed approach, the maximum value of the total profit appears, and this demonstrates the proposed approach is robust to maximize the total profit in surface-to-underground mining transition. This work contributes to existing literature studies primarily from practical aspect, by providing a unified approach to optimize the transition from surface to underground mining.

scholarly journals Mapping Annual Land Disturbance and Reclamation in a Surface Coal Mining Region Using Google Earth Engine and the LandTrendr Algorithm: A Case Study of the Shengli Coalfield in Inner Mongolia, China

2020 ◽  
Vol 12 (10) ◽  
pp. 1612 ◽  
Author(s):  
Wu Xiao ◽  
Xinyu Deng ◽  
Tingting He ◽  
Wenqi Chen
Keyword(s):  
Inner Mongolia ◽  
Land Reclamation ◽  
Underground Mining ◽  
Surface Mining ◽  
Mining Area ◽  
Google Earth ◽  
Open Pit ◽  
Open Pit Mining ◽  
Landsat Images ◽  
Google Earth Engine

The development and utilization of mining resources are basic requirements for social and economic development. Both open-pit mining and underground mining have impacts on land, ecology, and the environment. Of these, open-pit mining is considered to have the greatest impact due to the drastic changes wrought on the original landform and the disturbance to vegetation. As awareness of environmental protection has grown, land reclamation has been included in the mining process. In this study, we used the Shengli Coalfield in the eastern steppe region of Inner Mongolia to demonstrate a mining and reclamation monitoring process. We combined the Google Earth Engine platform with time series Landsat images and the LandTrendr algorithm to identify and monitor mining disturbances to grassland and land reclamation in open-pit mining areas of the coalfield between 2003 and 2019. Pixel-based trajectories were used to reconstruct the temporal evolution of vegetation, and sequential Landsat archive data were used to achieve accurate measures of disturbances to vegetation. The results show that: (1) the proposed method can be used to determine the years in which vegetation disturbance and recovery occurred with accuracies of 86.53% and 78.57%, respectively; (2) mining in the Shengli mining area resulted in the conversion of 89.98 km2 of land from grassland, water, etc., to barren earth, and only 23.54 km2 was reclaimed, for a reclamation rate of 26.16%; and (3) the method proposed in this paper can achieve fast, efficient identification of surface mining land disturbances and reclamation, and has the potential to be applied to other similar areas.

The Prediction of Northern Slope Deformation and Failure Caused by the Transformation of Open-Pit to Underground Mining in the Yanqianshan Iron Mine

2014 ◽  
Vol 580-583 ◽  
pp. 364-370
Author(s):  
An Lin Shao ◽  
Hai Long Feng
Keyword(s):  
Slope Failure ◽  
Underground Mining ◽  
Limit Equilibrium ◽  
Failure Process ◽  
Open Pit ◽  
Northern Slope ◽  
Body Distribution ◽  
Ore Bodies ◽  
Sublevel Caving ◽  
Iron Mine

<span><p class="TTPAbstract"><span lang="EN-US">The Yanqianshan<a name="OLE_LINK94"></a><a name="OLE_LINK93"></a> iron mine is preparing to transform from an open-pit mine to an underground mine. We adopt the <a name="OLE_LINK104"></a><a name="OLE_LINK103"></a>non-pillar sublevel caving approach to exploit the particularly thick steep ore bodies within the range from -183 m to -500 m from top to bottom. According to the features of ore body distribution and the approaches of exploitation, we expect that underground mining will result in <a name="OLE_LINK102"></a><a name="OLE_LINK101"></a>the loss of stability on the northern slope of the open pit, causing traction-type landslides. Moreover, along with increasing the depth of the mining operation, the range of slope failure will continue to expand and further affect the safety of drainage features and roads distributed on the north side of the open pit. For this purpose, we select f</span><span lang="EN-US">our</span><span lang="EN-US"> sections along the trending direction of ore bodies and apply the limit equilibrium method to predict the failure process and characteristics on the northern slope according to the stratified mining process.</span><span lang="EN-US"><o:p></o:p></span></p>

scholarly journals A New Mining Scheme for Hanging-Wall Ore-Body during the Transition from Open Pit to Underground Mining: A Numerical Study

2018 ◽  
Vol 2018 ◽  
pp. 1-17
Author(s):  
Baohui Tan ◽  
Fengyu Ren ◽  
Youjun Ning ◽  
Rongxing He ◽  
Qiang Zhu
Keyword(s):  
Underground Mining ◽  
Numerical Study ◽  
Hanging Wall ◽  
Slope Instability ◽  
Open Pit ◽  
Ore Body ◽  
Instability Development ◽  
Induced Caving ◽  
Iron Mine ◽  
Mining Scheme

A new mining scheme by employing the induced caving mining method to exploit hanging-wall ore-body during the transition from open pit to underground mining is proposed. The basic idea is to use the mined-out area generated by the planned mining of the hanging-wall ore-body to absorb the collapsed slope body, so as to avoid the influence of the inner-slope mining to the normal open-pit mining and guarantee mining efficiency during the transition stage. Numerical simulation study on the process of induced caving mining of hanging-wall ore-body is carried out based on the practical engineering setting of the Hainan iron mine, China, by employing the numerical method of discontinuous deformation analysis (DDA). The impact of rock mass structure on the mechanism of slope instability development and the mining hazard assessment in the new mining scheme is investigated. The influence of mining sequence on slope instability development and mining safety is also analyzed by taking the hanging-wall ore-body mining under the southern anti-dip slope at the Hainan iron mine as an example, and eventually a reliable mining scheme via induced caving is obtained. The numerical study proves the feasibility of the proposed new mining scheme for hanging-wall ore-body and provides theoretical and technical support for its application in practical mining activities.

Prediction of failure of south slope caused by underground mining in the Yanqianshan open-pit iron mine

2013 ◽  
pp. 391-397
Author(s):  
Xuebing Pei ◽  
Renjie Zhou ◽  
Nengxiong Xu ◽  
Xiaoqiang Liu ◽  
Jingping Liu
Keyword(s):  
Underground Mining ◽  
Open Pit ◽  
Iron Mine ◽  
South Slope

scholarly journals Study on End-wall Slope Stability of Surface Coal Mine under the Condition of Combined Open-pit Mining with Underground Mining

2016 ◽  
Vol 5 (2) ◽  
pp. 65
Author(s):  
Peng Hongge ◽  
Cai Qingxiang ◽  
Zhou Wei ◽  
Shu Jisen
Keyword(s):  
Coal Mine ◽  
Underground Mining ◽  
Surface Mining ◽  
Open Pit ◽  
Open Pit Mining ◽  
Surface Mine ◽  
Minimum Width ◽  
Surface Coal Mine ◽  
End Wall ◽  
Wall Slope

With the deepening of surface coal mine, the application of combined surface mining with underground mining is increased now. According to the influence analysis of underground mining on surface coal mine end-wall slope, the thin plate model of mined slope was proposed with distortion and stress distribution of the girder studied. Considering the practice of combined surface mining with underground mining, the modified method was put forward. Based on the roof breaking law of mined slope, the minimum width of protecting coal pillar was elicited. Subsequently this paper took the combined mining practice of Anjialing surface mine as example to study the subsidence law of roof and the influence of underground mining to surface mine slope. The research conclusion indicates that under the condition of combined mining the deformation and subsidence of overlying strata are obvious with a clear lag time, and the ceiling distortion evokes distortion of mined slope, which can be used as the theory sustainment to stabilization of mined slope under combined surface mining with underground mining.

scholarly journals Stability Analysis of Underground Multicavities in Bench Blasting Vibration

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Deqing Gan ◽  
Xi Yang ◽  
Yunpeng Zhang ◽  
Xinyu Wei
Keyword(s):  
Underground Mining ◽  
Open Pit ◽  
Open Pit Mining ◽  
Mining Activities ◽  
Potential Threat ◽  
Attenuation Relations ◽  
Bench Blasting ◽  
Iron Mine ◽  
Underground Cavities ◽  
The Stability

Underground cavities formed by underground mining activities are a potential threat to open-pit mining activities. Longtan Village Iron Mine is located in Chengde city, Hebei province, China. The open-pit mining and underground mining of Longtan Village Iron Mine are simultaneously performed. Cavities will remain after underground mining. When mining is performed on the top of the underground cavities in the open pit, concerns arise regarding the closest distance to prevent the collapse of the cavities. (The closest distance is the safe distance between the explosive and the cavities. If the distance between the explosive and the cavities is less than the closest distance, the stability of the cavities will be affected.) The collapse will endanger the safety of the workers and equipment in the open pit. Therefore, it is necessary to estimate the stability of the underground cavities near the bench blasting. In this paper, a series of bench blast tests was performed, and the site-specific attenuation relations of the PPV (Peak particle velocity) and principal frequency of Longtan Village Iron Mine were obtained. Then, an ANASYS three-dimensional numerical model was created, and the propagation of the blast wave and the response of the multicavities were calculated by LS-DYNA. The accuracy of the simulation was verified. However, the bench blast tests do not affect the stability of the cavities. The formula to calculate the closest distance was obtained, which can be used as an approximate guide when designing the bench explosion of Longtan Village Iron Mine. Workers can mine in a safe area of the open pit, and the stability of the cavities will not be affected.

scholarly journals Study on the Process and Mechanism of Slope Failure Induced by Mining under Open Pit Slope: A Case Study from Yanqianshan Iron Mine, China

2019 ◽  
Vol 2019 ◽  
pp. 1-26
Author(s):  
Yingpeng Hu ◽  
Fengyu Ren ◽  
Hangxing Ding ◽  
Yu Fu ◽  
Baohui Tan
Keyword(s):  
Slope Failure ◽  
Underground Mining ◽  
Ground Deformation ◽  
Failure Process ◽  
Google Earth ◽  
Open Pit ◽  
Mechanism Analysis ◽  
Eastern Slope ◽  
Rock Creep ◽  
Iron Mine

Mining under an open pit slope results in the collapse and slide of the slope. In this paper, a combination of methods including Google Earth and field investigations is applied to investigate the process of eastern slope failure induced by underground mining in the Yanqianshan Iron Mine over five years. According to the observed ground deformation features, the geomorphic zone of the eastern slope can be divided into four regions (caved rock zone, cracking zone, toppling zone, and sliding zone). Break angles and fracture initiation angles at different times are counted separately. Based on the above work, the process of initiation and development of slope failure is studied. The analysis results show that the process of slope failure could be chronologically divided into three stages. First, a collapse pit, caused by the falling of the overlying strata above the goaf, appeared on the eastern slope. Then, the rock mass around the collapse pit slid into the pit to form a small landslide. Finally, because of mining disturbances and rock creep, a large landslide occurred on the northeastern phyllite slope. The control mechanisms of each failure stage are discussed separately. Finally, the RFPA3D code is employed to simulate the slope failure process under the influence of underground mining. The results are consistent with the field observations, which provided information on deformation failure and the mechanics of the slope that could not be directly observed in the field and deepened the mechanism analysis.

Sign in / Sign up

Export Citation Format

Share Document