Haulage drifts play a vital role in providing personnel and equipment access to ore extraction areas for mine production. Thus, their stability is of crucial importance during the life of a mine plan. Many Canadian mi...Haulage drifts play a vital role in providing personnel and equipment access to ore extraction areas for mine production. Thus, their stability is of crucial importance during the life of a mine plan. Many Canadian mines use longhole mining methods or one of its variants. These methods require access to the orebody through haulage drifts on multiple levels. This paper examines the stability of mine haulage drifts with respect to planned mining sequence. A case study of an underground mine is presented. The case study examines # l Shear East of the Garson Mine in Sudbury, Ontario. A two-dimensional, elastoplastic, finite difference model （FLAC 2D） is developed for a haulage drift situated 1.5 km below surface in the footwall of the orebody. The stability of the haulage drift is evaluated in terms of the spread of yield zones into the rockmass due to nearby mining activities. The performance of the drift stability is evaluated at various mining stages, employing the RMC （Random Monte-Carlo） technique in conjunction with finite difference modeling to study the probability of unsatisfactory performance of the drift. The results are presented and categorized with respect to probability, instability and mining stage.展开更多
High time-stability performance of the injection kicker system is important for the Beijing Electron Positron Collider Upgrade Project (BEPCⅡ),with jitter and drift less than±5ns.In order to compensate the delay...High time-stability performance of the injection kicker system is important for the Beijing Electron Positron Collider Upgrade Project (BEPCⅡ),with jitter and drift less than±5ns.In order to compensate the delay time drift of thyratron on the kicker pulsed power supply,a drift stabilizer is developed.The test results meet the demand of design by regulation resolution=1ns,jitter+drift<2ns in 8 hours.The detailed design of the time-drift stabilizer will be described in this paper.展开更多
文摘Haulage drifts play a vital role in providing personnel and equipment access to ore extraction areas for mine production. Thus, their stability is of crucial importance during the life of a mine plan. Many Canadian mines use longhole mining methods or one of its variants. These methods require access to the orebody through haulage drifts on multiple levels. This paper examines the stability of mine haulage drifts with respect to planned mining sequence. A case study of an underground mine is presented. The case study examines # l Shear East of the Garson Mine in Sudbury, Ontario. A two-dimensional, elastoplastic, finite difference model （FLAC 2D） is developed for a haulage drift situated 1.5 km below surface in the footwall of the orebody. The stability of the haulage drift is evaluated in terms of the spread of yield zones into the rockmass due to nearby mining activities. The performance of the drift stability is evaluated at various mining stages, employing the RMC （Random Monte-Carlo） technique in conjunction with finite difference modeling to study the probability of unsatisfactory performance of the drift. The results are presented and categorized with respect to probability, instability and mining stage.
文摘High time-stability performance of the injection kicker system is important for the Beijing Electron Positron Collider Upgrade Project (BEPCⅡ),with jitter and drift less than±5ns.In order to compensate the delay time drift of thyratron on the kicker pulsed power supply,a drift stabilizer is developed.The test results meet the demand of design by regulation resolution=1ns,jitter+drift<2ns in 8 hours.The detailed design of the time-drift stabilizer will be described in this paper.
