Abstract
There are few studies on the management methods of large-scale goaf groups per the specific surrounding rock mass conditions of each goaf. This paper evaluates comprehensively the stability of the multistage large-scale goaf group in a Pb-Zn mine in Inner Mongolia, China, via the modified Mathews stability diagram technique. The volume of each goaf to be backfilled was quantitatively analyzed in the combination of theoretical analysis and three-dimensional laser scanning technology. The corresponding mechanical characteristics of the filling were determined by laboratory testing while formulating the treatment scheme of the large goaf group using the backfill method. The applicability of the treatment scheme using the backfill was verified by the combination of the numerical results of the distribution of the surrounding rock failure zone and the monitored data of the surface subsidence. The research results and treatment scheme using the backfill can provide a reference for similar conditions of mines worldwide.
Highlights
Engineering BackgroundThere are four surface subsidence areas and a total of six subsidence pits
It is easy to cause a variety of mine disasters, such as roof caving [3], surface subsidence [4], rib failure [5], and water inrushing [6], resulting in irretrievable casualties and property losses [7]. e essence of the safety management of a large goaf group is to transfer the stress concentration, ease the stress concentration on the rock mass or make the stress state reach a new relative balance, and ensure the mines’ pressure and their secure productions [8, 9]
One can observe that the failure area of the nearby rock of the goaf is significantly reduced after using the backfill method per the deformation state of the nearby rock mass, and the backfill treatment of the goaf significantly improves the stability of the surrounding rock mass
Summary
There are four surface subsidence areas and a total of six subsidence pits. E main reasons for the collapse are the goaf above the 808m level in the western area, the oxidation of some ore bodies near the surface, broken surrounding rock on the hanging wall, the fact that the mining method is mostly the sublevel open stoping method of mid-hole caving, and a strong broken zone that is produced nearby There are four surface subsidence areas and a total of six subsidence pits. e subsidence area of the F1 fracture zone of the lines 3 to 5, 5526 m2 of the lines 9 to 13, 16,237 m2 of the lines 25 to 29, and 2100 m2 of the F3 fracture zone of the lines 53 to 57 is located in the delineated mobile zone as shown in Figure 1. e main reasons for the collapse are the goaf above the 808m level in the western area, the oxidation of some ore bodies near the surface, broken surrounding rock on the hanging wall, the fact that the mining method is mostly the sublevel open stoping method of mid-hole caving, and a strong broken zone that is produced nearby
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
