Rockbursts in longwall gates during coal mining in Ostrava-Karviná coal basin

The analysis of rockbursts effects in Ostrava-Karviná Coalfield has indicated a principal difference between effects of rockbursts on gates and effects on longwall faces. The effects on gateways are distinctly more intense even if they occur at lower energy level of dynamic events. Mostly opened support structures in gateroads are concerned with relatively low resistance against dynamic loading from roadway side and floor (such load is most frequent in case of rockbursts). The proper reinforcing measures must include a reinforcing of steel support structure and influencing of phisico-mechanical characteristics of rocks and coal in roadway surroundings (reinforcement by grouting and bolting).