深埋高应力区巷道冲击地压预测与防治方法研究

STUDY ON FORECAST AND PREVENTION METHODS FOR ROCKBURST OF DEEP ROADWAY WITH HIGH GEOSTRESS

对平煤集团十二矿三水平皮带下山冲击地压预测与防治方法进行研究。结果表明,皮带下山所处位置构造复杂,以构造应力为主,地应力较大,属于深埋巷道。皮带下山围岩属典型的高强脆性岩石,具有中等偏强冲击倾向性。采用电磁辐射方法监测结果与实际发生冲击地压的情况基本一致,电磁辐射强度临界值为30mV,脉冲数临界值为400000次。电磁辐射指标超过临界值时具有冲击地压危险地段,采用拱顶浅孔爆破卸压法治理措施后,电磁辐射指标有明显下降,冲击地压的强度、频度均有所减弱和减少,有效地缓解和防治冲击地压发生的作用。巷道掘进施工采用短段掘锚作业,及时锚网喷索联合支护,打眼施工期间挂设防护网,最大限度地消除和缓解冲击地压的危害。

Forecast and prevention methods were studied for rockburst in haulage-dip at Coal Mine No.12, Pingdingshan Coal Group of China. This haulage-dip belongs to a deep roadway with the complex geological conditions, and the tectonic stresses are very high. The surrounding rock of the haulage-dip is a typical brittle rock with high strength and is a middle burst-prone mine. The in-situ monitoring results for rockburst with electromagnetic emission method（EEM） were basically consistent with practical situation. The critical value of EEM was 30 mV and the critical value of pulse count was 400 000. When the magnitude of EEM in the roadway area exceeded the critical value, the rockburst occured in this danger area of haulage-dip. After the shallow blasting measures were taken; the pressure over roadway roof was released, and the magnitude of EEM obviously decreased. The intensity and frequency of rockburst were also reduced. Therefore, rockburst can be effectively prevented. Short-range excavation, bolt supporting with shotcrete in-time and hanging steel net during roadway excavation can reduce or lessen the hazard of rock burst.