Technical gazette, Vol. 22 No. 1, 2015.
Original scientific paper
https://doi.org/10.17559/TV-20141130115523
A novel backfill material for roof supports in the cut-through entries of longwall mining
Jingyi Cheng
; Department of Mining Engineering, West Virginia University, Statler College of Engineering and Mineral Resources, 169 Mineral Resources Building, P.O. Box 6070, Morgantown, WV 26506-6070, United States
Wenfeng Li
; Department of Mining Engineering, West Virginia University, Statler College of Engineering and Mineral Resources, 169 Mineral Resources Building, P.O. Box 6070, Morgantown, WV 26506-6070, United States
Peng Zhang
orcid.org/0000-0001-6618-834X
; Carlson Software, 480 Pleasant St, Suite C100, Watertown, MA 02472, United State
Abstract
To enhance underground mining safety, researchers developed high-water and fast-setting cement (HWFSC). HWFSC essentially consists of two components and can be mixed with large quantities of water. To determine its mechanical strength, a series of uniaxial compressive strength tests were conducted on HWFSC specimens with different water-to-solid ratios. Results indicate that peak strength declined significantly with the increase in W/S ratio, whereas residual strength increased gradually with this enhancement. The feasibility of backfilling cut-through entries with HWFSC is then evaluated through a case study. The LaModel program was used to assess the yielding of the fender pillar and the deformation of the cut-through entry. Results also show that the use of HWFSC to backfill the cut-through entry addressed complicated ground control problems effectively. Further analysis also suggested that HWFSC was the optimal backfill material in terms of both economic cost and roof support safety.
Keywords
backfill material; cut-through entry; field monitoring; high-water and fast-setting cement (HWFSC); numerical modelling; roof support
Hrčak ID:
135082
URI
Publication date:
23.2.2015.
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