Open pit slope stability analysis in soft rock formations at Thar Coalfield Pakistan

• Autorzy: Pathan Shafi Muhammad , Pathan Abdul Ghani , Siddiqui Fahad Irfan , Memon Muhammad Burhan , Soomro Mairaj Hyder Alias Aamir

Identyfikatory

DOI

10.24425/ams.2022.142409

• Języki publikacji: EN

Abstrakty

EN

Slope Stability Analysis is one of the main aspects of Open-pit mine planning because the calculations regarding the stability of slopes are necessary to assess the stability of the open pit slopes together with the financial feasibility of the mining operations. This study was conducted to analyse the effect of groundwater on the shear strength properties of soft rock formations and determine the optimum overall slope angle for an open pit coal mine at Thar Coalfield, Pakistan. Computer modelling and analysis of the slope models were performed using Slide (v. 5.0) and Phase2 (v. 6.0) software. Integrated use of Limit Equilibrium based Probabilistic (LE-P) analysis and Finite Element Method (FEM) based shear strength reduction analysis was performed to determine the safe overall slope angle against circular failure. Several pit slope models were developed at different overall slope angles and pore-water pressure ratio (Ru) coefficients. Each model was initially analysed under dry conditions and then by incorporating the effect of pore-water pressure coefficients of Ru = 0.1, 0.2, and 0.3 (partially saturated); finally, the strata were considered to be fully saturated. It was concluded that at an overall slope angle of 29 degrees, the overall slope will remain stable under dry and saturated conditions for a critical safety factor of 1.3.

Słowa kluczowe

EN

open pit slope stability; overall slope angle; Thar Coalfield; computer modelling

PL

szyb górniczy; skała osadowa; modelowanie komputerowe

• Wydawca: Instytut Mechaniki Górotworu PAN
• Czasopismo: Archives of Mining Sciences
• Rocznik: 2022
• Tom: Vol. 67, no. 3
• Strony: 437--454
• Opis fizyczny: Bibliogr. 32 poz., fot., rys., tab., wykr.

Twórcy

autor

Pathan Shafi Muhammad

• Mehran University of Engineering and Technology, Department of Mining Engineering, Jamshoro, Pakistan

• https://orcid.org/0000-0002-5206-9611

autor

Pathan Abdul Ghani

• Mehran University of Engineering and Technology, Department of Mining Engineering, Jamshoro, Pakistan

• https://orcid.org/0000-0003-0031-1856

autor

Siddiqui Fahad Irfan

• Mehran University of Engineering and Technology, Department of Mining Engineering, Jamshoro, Pakistan

• https://orcid.org/0000-0002-2094-2236

autor

Memon Muhammad Burhan

• Mehran University of Engineering and Technology, Department of Mining Engineering, Jamshoro, Pakistan

• https://orcid.org/0000-0001-7146-9875

autor

Soomro Mairaj Hyder Alias Aamir

• Mehran University of Engineering and Technology, Department of Mining Engineering, Jamshoro, Pakistan

• https://orcid.org/0000-0002-4424-6921

Bibliografia

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Uwagi

PL

Opracowanie rekordu ze środków MEiN, umowa nr SONP/SP/546092/2022 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2022-2023)