Blasting in geological bodies is an industrial process acting in an environment characterized by high uncertainties (natural joints, faults, voids, abrupt structural changes), which are transposed into the process par...Blasting in geological bodies is an industrial process acting in an environment characterized by high uncertainties (natural joints, faults, voids, abrupt structural changes), which are transposed into the process parameters (e.g. energetic transfer to rock mass, hole deviations, misfires, vibrations, fly-rock, etc.). The approach to this problem searching for the "optimum" result can be ineffective. The geological environment is marked out by too many uncertainties, to have an "optimum" suitable to different applications. Researching for "Robustness" in a blast design gives rise to much more efficiency. Robustness is the capability of the system to behave constantly under varying conditions, without leading to unexpected results. Since the geology varies from site to site, setting a robust method can grant better results in varying environments, lowering the costs and increasing benefits and safety. Complexity Analysis (C.A.) is an innovative approach to systems. C.A. allows analyzing the Complexity of the Blast System and the criticality of each variable (drilling, charging and initiation parameters). The lower is the complexity, the more robust is the system, and the lower is the possibility of unexpected results. The paper presents the results obtained thanks to the C.A. approach in an underground gypsum quarry (Italy), exploited by conventional rooms and pillars method by drilling and blasting. The application of C.A. led to a reliable solution to reduce the charge per delay, hence reducing the impact of ground vibration on the surrounding structures. The analysis of the correlation degree between the variables allowed recognizing empirical laws as well.展开更多
On the basis of Mises strength theory,rock models are built including vertical,horizontal and diagonal joints to simulate jointed rock mass under blasting load by using FEM. The dynamic procedures of jointed rock mass...On the basis of Mises strength theory,rock models are built including vertical,horizontal and diagonal joints to simulate jointed rock mass under blasting load by using FEM. The dynamic procedures of jointed rock mass under blasting are quantified and the effective stress-time curves of typical elements are compared to analyze the barrier of joints to the stress wave. The blasting law was studied according to the process of computer simulation and the effect of blasting,and some suggestions were given for solving the problems of overbreak and underbreak.展开更多
文摘Blasting in geological bodies is an industrial process acting in an environment characterized by high uncertainties (natural joints, faults, voids, abrupt structural changes), which are transposed into the process parameters (e.g. energetic transfer to rock mass, hole deviations, misfires, vibrations, fly-rock, etc.). The approach to this problem searching for the "optimum" result can be ineffective. The geological environment is marked out by too many uncertainties, to have an "optimum" suitable to different applications. Researching for "Robustness" in a blast design gives rise to much more efficiency. Robustness is the capability of the system to behave constantly under varying conditions, without leading to unexpected results. Since the geology varies from site to site, setting a robust method can grant better results in varying environments, lowering the costs and increasing benefits and safety. Complexity Analysis (C.A.) is an innovative approach to systems. C.A. allows analyzing the Complexity of the Blast System and the criticality of each variable (drilling, charging and initiation parameters). The lower is the complexity, the more robust is the system, and the lower is the possibility of unexpected results. The paper presents the results obtained thanks to the C.A. approach in an underground gypsum quarry (Italy), exploited by conventional rooms and pillars method by drilling and blasting. The application of C.A. led to a reliable solution to reduce the charge per delay, hence reducing the impact of ground vibration on the surrounding structures. The analysis of the correlation degree between the variables allowed recognizing empirical laws as well.
文摘On the basis of Mises strength theory,rock models are built including vertical,horizontal and diagonal joints to simulate jointed rock mass under blasting load by using FEM. The dynamic procedures of jointed rock mass under blasting are quantified and the effective stress-time curves of typical elements are compared to analyze the barrier of joints to the stress wave. The blasting law was studied according to the process of computer simulation and the effect of blasting,and some suggestions were given for solving the problems of overbreak and underbreak.
