modeling horizontal insitu stress with flac3d

Proceedings, 25th International Conference on Ground Control in Mining, Morgantown, WV, 2006. Horizontal stress and coal mines: twenty five years of experience and perspective. The modeling approach described in this paper can be used as a tool to evaluate potential roof failure and optimize the stability of room and pillar layouts.ġ. The effects of high horizontal stresses can be mitigated by orientating the heading development direction parallel to the maximum horizontal stress, reducing the number of cross-cuts and offsetting the cross-cuts to limit the potential lateral extent of horizontal stress related roof falls. Numerical analyses show that the pillar layout and orientation of the mine workings have an effect on the horizontal stress distribution within the roof. Horizontal stress related damage can occur in the form of guttering along one or more sides of an excavation, roof beam buckling or oval shaped roof falls, with the long axis perpendicular to the major horizontal stress. Rockfalls are the cause of 15% of all reportable injuries in underground limestone mines. The stability of these excavations can be compromised by the horizontal stress, resulting in a rockfall hazard. Underground limestone mines use the room-and-pillar method, in which 12- to 18-m-wide rooms are typically excavated. Limestone formations in the United States can be subject to relatively high horizontal stresses due to the existence of tectonic loading of the limestone strata.

National Institute for Occupational Safety and Health, USA Field observations and numerical studies of horizontal stress effects on roof stability in US limestone mines

Modeling horizontal insitu stress with flac3d