Effect of an eccentric decoupled charge on rock mass blasting

• Autorzy: Kim Jung-Gyu , Ali Mahrous A.M. , Kim Jong-Gwan

Identyfikatory

DOI

10.46873/2300-3960.1000

• Języki publikacji: EN

Abstrakty

EN

Experimental and numerical analyses were conducted to investigate the effect of an eccentric loaded contour hole on a rock mass. In the concrete blocks used for the analyses, detonating cords were placed at the centre of the blast hole and eccentrically against the wall of the blast hole. PFC2D and AUTODYN were used for the numerical analyses, and the results of these software showed that an eccentric decoupled charge can result in the directional development of fractures, thereby enabling the control of cracks in the opposite direction. Even though both types of blasting have identical decoupling indexes, the crack and fracture patterns were affected by the location of the explosive, tamping, and other conditions. The results showed that an eccentric charge holder can be applicable to control the fracture direction and the damaged zone. For an eccentric charge, the initial crack was generated at 0.01 ms and expanded in the intended direction. For the eccentric charge, the maximum pressure at the area in contact with the blast hole wall exceeded that for the central decoupled charge by a factor of 5.5. Furthermore, the pressure in the intended direction was twice of that in the opposite direction.

Słowa kluczowe

EN

eccentric decoupled charge; fracture pattern; PFC; AUTODYN; decoupling index

PL

wzór pęknięcia; PFC; AUTODYN; wskaźnik odsprzęgania

• Wydawca: Elsevier ; Główny Instytut Górnictwa
• Czasopismo: Journal of Sustainable Mining
• Rocznik: 2020
• Tom: Vol. 19, iss. 1
• Strony: 1--10
• Opis fizyczny: Bibliogr. 24 poz.

Twórcy

autor

Kim Jung-Gyu

• Department of Energy and Resources Engineering, Chonnam National University, Korea

autor

Ali Mahrous A.M.

• Mining and Petroleum Eng. Depart, Faculty of Engineering- Al-Azhar University, Qena, Egypt

autor

Kim Jong-Gwan

• Department of Energy and Resources Engineering, Chonnam National University, Korea

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