110 / 2021-09-30 14:18:06

Advanced engineering tools for mine shaft design, construction and monitoring

shaft design,monitoring,artificial ground freezing,numerical calculations

For the purpose of shaft design, various approaches may be used based on analytical, empirical or numerical methods. Especially the numerical approach has become increasingly common, mostly for analysis of site-specific complex conditions in the later phases of engineering design. However, regardless of the selected method of designing the shaft liner, the temporary support or the groundwater control methodology, the rock mass parameters are derived from available data from in-situ and laboratory testing. In many cases, the selection of the derivation methodology needs to be adjusted according to the type of information collected during in-situ investigation campaigns. For example, if there is not enough data for the RMR (Rock Mass Rating) classification available (e.g. no field strength or joint spacing were logged), other methods (e.g. Q-System) need to be considered to estimate the missing components. The above aspects represent one of the main sources of uncertainties during mine shaft design and construction. Another source of error is the inaccuracies of the design tools, e.g. due to required mathematical simplifications in analytical methods or to approximation errors in numerical methods. A third one is the description of the ground conditions limited to a small area only. In most cases, the investigations performed at the start of a new shaft are based on the analysis of rock and soil probes obtained from boreholes. It is not uncommon that the ground conditions during shaft sinking may differ from the ones taken as design basis, which affects the estimated stress and strain state of the shaft lining. Therefore, it is extremely important to use tools which minimize such discrepancy and to include into the shaft design a monitoring system to collect sufficient data enabling control of important phenomena, not only during shaft sinking but also during the life of the shaft. Such technology is an automated shaft monitoring system with numerous advantages, not only increasing safety and productivity but also reducing costs. The continuous collection of new data from laser measurements makes it possible to extend an idealized numerical model with such important information as the existing overbreak and other as-built details. In this way, the reliability of the simulation increases and the impact of the mining operations may be better assessed (Figure 1).



Nowadays, the amount of collected data is rapidly growing. It is necessary not only in order to manage any unexpected events like rock mass deformations during shaft sinking, but also to collect monitoring data, supervise any changes of specific design requirements, design codes, submissions guidelines, review checks of design documentation and other multi-disciplinary coordination.



This paper presents an overview of available engineering solutions and describes the requirements of advance engineering tool for mine shaft design, construction and monitoring.

For the purpose of shaft design, various approaches may be used based on analytical, empirical or numerical methods. Especially the numerical approach has become increasingly common, mostly for analysis of site-specific complex conditions in the later phases of engineering design. However, regardless of the selected method of designing the shaft liner, the temporary support or the groundwater control methodology, the rock mass parameters are derived from available data from in-situ and laboratory testing. In many cases, the selection of the derivation methodology needs to be adjusted according to the type of information collected during in-situ investigation campaigns. For example, if there is not enough data for the RMR (Rock Mass Rating) classification available (e.g. no field strength or joint spacing were logged), other methods (e.g. Q-System) need to be considered to estimate the missing components. The above aspects represent one of the main sources of uncertainties during mine shaft design and construction. Another source of error is the inaccuracies of the design tools, e.g. due to required mathematical simplifications in analytical methods or to approximation errors in numerical methods. A third one is the description of the ground conditions limited to a small area only. In most cases, the investigations performed at the start of a new shaft are based on the analysis of rock and soil probes obtained from boreholes. It is not uncommon that the ground conditions during shaft sinking may differ from the ones taken as design basis, which affects the estimated stress and strain state of the shaft lining. Therefore, it is extremely important to use tools which minimize such discrepancy and to include into the shaft design a monitoring system to collect sufficient data enabling control of important phenomena, not only during shaft sinking but also during the life of the shaft. Such technology is an automated shaft monitoring system with numerous advantages, not only increasing safety and productivity but also reducing costs. The continuous collection of new data from laser measurements makes it possible to extend an idealized numerical model with such important information as the existing overbreak and other as-built details. In this way, the reliability of the simulation increases and the impact of the mining operations may be better assessed (Figure 1).



Nowadays, the amount of collected data is rapidly growing. It is necessary not only in order to manage any unexpected events like rock mass deformations during shaft sinking, but also to collect monitoring data, supervise any changes of specific design requirements, design codes, submissions guidelines, review checks of design documentation and other multi-disciplinary coordination.



This paper presents an overview of available engineering solutions and describes the requirements of advance engineering tool for mine shaft design, construction and monitoring.