Effect of in situ horizontal stresses on roadway stability

The effect of in situ horizontal stresses on coal mine roadways stability has been reported in several publications in the literature. On most of the occasions, the instability was attributed to major horizontal in situ stress acting at a particular direction with reference to the roadway. In the present paper the authors have dealt with a case study where the instability in one set of the roadways was found to be due to the maximum horizontal in situ stress. In the absence of actual in situ stress measurement data, the maximum in situ horizontal stress was estimated from a detailed geotechnical study. A 3D finite difference soffware, FLAC 3D, has been used to investigate the proper orientation of the dip-rise roadways and support requirement for long-term stability of the main roadways.