Fundamental principles of rock fracturing at the vicinity of preconditioned blast hole

• Autorzy: Sengani Fhatuwani

Identyfikatory

DOI

10.24425/ams.2020.134146

• Języki publikacji: EN

Abstrakty

EN

A simple empirical study on the orientation, diameter, and extent of radial fractures (long and short) at the vicinity of the face-perpendicular preconditioned boreholes is described. Homogenous and hete-rogeneous mining faces were considered when studying the orientation of radial fractures, four and five face-perpendicular preconditioning practices were used to investigate the outspread and diameter of radial fractures from one blasted drill hole to another. Long radial fractures were observed to be developed along the direction of the maximum principal stress and short radial fractures were observed to be developed along the direction of the intermediate principal stress in a homogenous mining face. On the other hand, long radial fractures were observed to be developed along the direction of the intermediate principal stress, while short radial fractures were observed to be developed along the direction of the maximum principal stress when the mining faces subjected to heterogeneous rock mass. The diameters of the radial fractures observed were inconsistent and were not nine times the diameter of the original borehole. Fur-thermore, the extent of radial fractures from one borehole to another was noted to be gradually improved when the additional of preconditioned borehole was in place. This study maintained that the orientation of radial fractures is mostly controlled by the rock properties, however, extend and the diameters of the radial fractures are controlled by rock properties, the effectiveness of the stress wave and gas pressure and brittleness of the rock mass.

Słowa kluczowe

EN

radial fractures; Face-perpendicular preconditioning; heterogeneous rock mass; homogenous rock mass; orientation of radial fractures

PL

pęknięcie; górotwór; otwór wiertniczy

• Wydawca: Instytut Mechaniki Górotworu PAN
• Czasopismo: Archives of Mining Sciences
• Rocznik: 2020
• Tom: Vol. 65, no. 4
• Strony: 769--786
• Opis fizyczny: Bibliogr. 74 poz., fot., rys., tab.

Twórcy

autor

Sengani Fhatuwani

• Eology and Mining, University of Limpopo, Sovenga, 0727, Polokwane, South Africa

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Uwagi

PL

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2021)