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
Railway induced vibrations and noises are a growing matter of environmental concern. The rapid development of transportation and increases in vehicle speeds and vehicle weights have resulted in higher vibration and no...Railway induced vibrations and noises are a growing matter of environmental concern. The rapid development of transportation and increases in vehicle speeds and vehicle weights have resulted in higher vibration and noise levels. In the meantime vibrations and noises that seem to have been tolerated in the past, are now more often considered to be a nuisance. Methodology of assessing ground-borne vibrations for railway traffic is presented based on the Federal Railway Administration （FRA） Guidance Manual-High-Speed Ground Transportation Noise and Vibration Impact Assessment. Effectiveness of wave barriers such as open trench, in-filled trench, and piers for reduction of vibrations induced by railways and the procedure for barrier selection are discussed. Finally, an example of vibration assessing of Suvarnabhumi Airport Rail Link is presented to demonstrate the methodology.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.
基金Acknowledgments The work reported herein was supported by the Special Program for International Cooperation and Exchange of the Ministry of Science and Technology, China （No. 2010DFA82340）, and the Natural Science Foundation of China （No. 50978099）.
文摘Railway induced vibrations and noises are a growing matter of environmental concern. The rapid development of transportation and increases in vehicle speeds and vehicle weights have resulted in higher vibration and noise levels. In the meantime vibrations and noises that seem to have been tolerated in the past, are now more often considered to be a nuisance. Methodology of assessing ground-borne vibrations for railway traffic is presented based on the Federal Railway Administration （FRA） Guidance Manual-High-Speed Ground Transportation Noise and Vibration Impact Assessment. Effectiveness of wave barriers such as open trench, in-filled trench, and piers for reduction of vibrations induced by railways and the procedure for barrier selection are discussed. Finally, an example of vibration assessing of Suvarnabhumi Airport Rail Link is presented to demonstrate the methodology.
