Reliability analysis of the induced damage for single-hole rock blasting |
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| Authors: | Mahdi Shadab Far Yuan Wang Yousif A H Dallo |
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| Institution: | 1. Department of Geotechnical Engineering, Tongji University, Shanghai, People's Republic of China;2. School of Civil and Transportation Engineering, Hohai University, Nanjing, People's Republic of China;3. College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing, People's Republic of China |
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| Abstract: | Rock explosion has always been a complex problem because neither rock characteristics nor explosion waves could be accurately estimated. As such, this imposes a high uncertainty on deterministic methodologies available for damage prediction. In this paper, by defining two damage zones around the blast hole, including crushed and cracked zones, a first-order reliability analysis (FORM) was adopted to address this issue. For this purpose, FORM was used in a double-loop algorithm, where the inner loop was responsible for converging the FORM, and the outer loop was assigned to feed the inner loop with new cases. Using such nested-loop algorithm, the probability of exceedance was calculated for any desired damage zone radius. The maximum effect of the involved parameters on the failure probability induced around the blast hole was additionally studied using a parametric reliability analysis. The results showed that the radii for crushed and cracked zones are limited to 0.5 and 4.2?m, respectively, so that the probability of going beyond these limits is less than 1%. Moreover, the analyses of decoupled explosions showed that increasing the gap between the explosion charge and wall of the borehole could severely reduce the failure probability; however, the maximum effect of decoupling ratio occurs in the small range of radii between 0.3?mm and 2.35?m. |
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| Keywords: | Damage zone first-order reliability method (FORM) Monte Carlo method exceedance risk curve failure probability |
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