Stability Evaluation of Old and Unapproachable Underground Mine Workings below Surface Structures

Abstract

There are many places in the different countries of the world where working in the underground mines have been done below surface structures such as railway lines, roads, buildings, villages/residential colonies, pipelines, etc. The workings are generally old, abandoned and presently unapproachable. In some places, important delicate surface structures are installed above a portion of old abandoned underground workings. Safety of these important surface structures above old underground mine workings is a serious concern in many countries all over the world. Many times, it is difficult to move or divert these surface structures due to a number of reasons including technical problems, the involvement of huge expenditures and socio-economic issues. There is a need to assess the stability of these places and the procedure to stabilise the places if found unstable to make the structures safe. Hence, there is a need of proper stability assessment of the ground below these surface structures. The railway line is one of such important structures, where stability should be ensured for the safety of the passengers. In India, many underground workings are present below railway lines. Most of the workings are old and unapproachable and their stability status is in doubt. Dismantling or diverting of the important railway lines is a high-level policy matter and involves huge time and money besides complicated socio-political issues like the rehabilitation of the affected people. But the safety of the commuters using railways passing over the coal-bearing areas having mining activities cannot be compromised. Therefore, it is highly preferable to take protective measures instead of dismantling and diversion of lines, wherever possible. It is necessary to establish the position and dimension of the inaccessible underground workings below these types of important surface structures and carry out its stability analysis to take appropriate protective measures for the safety of the structures and commuters. This paper highlights the delineation procedure of the unapproachable underground roadways below surface structures with special reference to railway lines and its stability evaluation with case studies. Appropriate protective measures have also been suggested which are proved to be effective and validated the results of the study.

Pumped Storage Hydropower in Abandoned Mine Shafts: Key Concerns and Research Directions

“…Meanwhile, there will be about 15,000 sites suitable for building mineshaft-based PSH plants, with an installed capacity of approximately 1800 GW. These statistics suggest a huge market potential [30][31][32]. The PSH plant reallocates the electric generation capacity of the power system temporally and reconciles the contradictions between power generation and power consumption.…”

“…Meanwhile, there will be about 15,000 sites suitable for building mineshaftbased PSH plants, with an installed capacity of approximately 1800 GW. These statistics suggest a huge market potential [30][31][32]. The National Energy Administration has explicitly pointed out in the Pumped Storage Medium and Long-Term Development Plan 2021-2035 that ʺPSH plants fulfill multiple functions, including peak regulation, valley filling, frequency regulation, phase regulation, energy storage, backup for accidents, and black start.…”

“…Meanwhile, there will be about 15,000 sites suitable for building mineshaft-based PSH plants, with an installed capacity of approximately 1800 GW. These statistics suggest a huge market potential [30][31][32].…”

Study on Control Technology for Working Faces Passing through Long-Span Abandoned Roadways

“…In recent years, experts and scholars worldwide have performed research on rock failure and rock bridge coalescence related to mining engineering. In particular, many rock mechanics studies related to exposed abandoned roadways in working faces have been performed [5][6][7][8][9][10][11][12][13]. Zhang et al [5] proposed that due to the existence of an abandoned roadway, the working face roof exhibited further developed fracture characteristics, while the supporting stress was noticeably concentrated at the pillar.…”

“…Ma and Wang [6] used UDEC to establish a numerical model, which indicated that a bearing arch existed in the cataclastic regenerated roadway roof and that the arch rise underwent changes with an increase in the roof hanging time and with different support scenarios, and proposed an optimal roof support approach to control abandoned roadways. Kushwaha et al [7] evaluated the safety of surface structures above old underground mine workings and proposed appropriate protective measures. Zhou et al [8] analyzed the distribution law of gas on abandoned roadways and proposed surface-based radon detection to identify spontaneous combustion areas in the gobs of small coal mines.…”