Stability Analysis of Rib Pillars in Highwall Mining Under Dynamic and Static Loads in Open-Pit Coal Mine

Abstract The highwall miner can be used to mine the retained coal in the end slope of an open-pit mine. However, the instability mechanism of the reserved rib pillar under dynamic and static loads is not clear, which restricts the safe and efficient application of the highwall mining system. In this study, the load-bearing model of the rib pillar in highwall mining was established, the cusp catastrophe theory and the safety coefficient of the rib pillar were considered, and the criterion equations of the rib pillar stability were proposed. Based on the limit equilibrium theory, the limit stress of the rib pillar was analyzed, and the calculation equations of plastic zone width of the rib pillar in highwall mining were obtained. Based on the Winkler foundation beam theory, the elastic foundation beam model composed of the rib pillar and roof under the highwall mining was established, and the calculation equations for the compression of the rib pillar under dynamic and static loads were developed. The results show that with the increase of the rib pillar width, the total compression of the rib pillar under dynamic and static loads approximately decreases in an inverse function, and the compression of the rib pillar caused by static loads of the overlying strata and trucks has a decisive role. Numerical simulation and theoretical calculation were performed in this study. In the Numerical simulation, the coal seam with a buried depth of 122 m and a thickness of 3 m was mined by the highwall miner. According to the established rib pillar instability model of the highwall mining system, it is found that when the mining tunnel width is 3 m, the reasonable width of the rib pillar is at least 1.3 m, and the safety factor of the rib pillar is 1.3. The numerical simulation results are in good agreement with the results of theoretical calculation, which verifies the feasibility of the theoretical analysis of the rib pillar stability. The research results can provide an important reference for the stability analysis of rib pillars under highwall mining.

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Structural Stability Analysis of High-Rise Building Transfer Beam High-Formwork Supporting System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.151.291 ◽

2012 ◽

Vol 151 ◽

pp. 291-294

Author(s):

Jian Hua Cui ◽

Ping Liu

Keyword(s):

Numerical Simulation ◽

Stability Analysis ◽

Theoretical Calculation ◽

Real Time ◽

Structural Stability ◽

Real Time Monitoring ◽

Supporting System ◽

High Rise ◽

High Rise Building ◽

Integral Stability

Based on the construction of the transfer floor of Yunding project in Chengdu, to solve the issues from the integral stability and safety of the transfer beam high-formwork supporting system, the method of the theoretical calculation, the method of the numerical simulation and real-time monitoring were applied in order to make some conclusions. The conclusions will be significance to apply in the future similar projects for reference and guidance.

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Slope Stability Analysis Based on Safety Factors on Slope CV. Mutiara Timur in Klampok Village, Tongas District, Probolinggo Regency

Journal of Earth and Marine Technology (JEMT) ◽

10.31284/j.jemt.2021.v2i1.2168 ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Yazid Fanani ◽

Aprilia Dwi Astuti ◽

Andres Kevi Paki

Keyword(s):

Stability Analysis ◽

Slope Stability ◽

Safety Factor ◽

Slope Stability Analysis ◽

Open Pit ◽

Open Pit Mining ◽

Mining System ◽

A Company ◽

Rock Lithology ◽

Safe Working

CV. Mutiara Timur is a company that is applying for a mining business permit for sirtu commodities in Klampok Village, Tongas District, Probolinggo Regency. The planned mining system is open pit mining using the quarry method. From the results of research in the field obtained rock lithology in the form of topsoil, gravel and sand. Where in the slope design later, the topsoil will be peeled off first. The purpose of slope stability analysis is to determine the geometry of the slope by taking into account the safety factor in order to create safe working conditions. Slope stability analysis on CV. Mutiara Timur using the Bishop method using the Slide v6.0 software. Based on the analysis carried out, the recommendation for slope geometry on a single slope is 4 meters high with a slope of 600 so that the no-load safety factor is 1.350 and the safety factor with load is 1.267. In addition, the slope geometry is obtained on the overall slope, which is a total height of 21 meters with a slope of 380 so that the no-load safety factor is 1.243 and the safety factor with the load is 1.239.

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Study on Web Pillar Stability in Open-Pit Highwall Mining

10.21203/rs.3.rs-847254/v1 ◽

2021 ◽

Author(s):

Juyu Jiang ◽

Zhuowei Zhang ◽

Dong Wang ◽

Laigui Wang ◽

Xinping Han

Keyword(s):

Ultimate Strength ◽

Coal Pillar ◽

Open Pit ◽

Instability Criterion ◽

Pillar Width ◽

Mining Technology ◽

Pillar Stability ◽

Yield Zone ◽

Highwall Mining ◽

The Web

Abstract When highwall mining technology is applied to recover large amounts of residual coal left under the highwall of a big open-pit mine, reasonable coal pillar width is the premise for maintaining the stability of web pillars. By adopting the numerical simulation method, the characteristics of the abutment stress distributions in the web pillars under different slope angles and mining depths are studied, and the function of the stress distribution in the web pillar is established. The relationship between the abutment stress and the ultimate strength of the web pillar under different widths is also analyzed and used in combination with the failure characteristics of the pillar yield zone to explore the instability mechanism of the web pillar. The retaining widths of the web pillars are determined. Based on the modeling results, a mechanical bearing model of the web pillar is established, a cusp catastrophe model of pillar-overburden is constructed, and the formula for the web pillar instability criterion is obtained. By analyzing and calculating the ultimate strength of the web pillar, the formula for calculating the yield zone width at both sides of the pillar is achieved. Using the instability criterion of web pillars in highwall mining, a reasonable pillar width can be deduced theoretically, which provides significant guidance on the application of highwall mining technology.

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