Takes a coal mine shaft uncovering outburst coal seam as prototype,builds calculating model by using FLAC3D software.The results show that under the shaft uncovering coal face is a funnel -shape stress relief zone,the stress relief degree gradually decreases from the shaft center to the surrounding.When around the shaft,before and after the shaft workface appear the stress concentration area,and the shaft is apart from the coal seam 5 meters,two sides of the coal seam begin to appear stress concentration zone,the stress concentration zone range from outside the shaft is 4 m to 6 m.After the shaft dig into the coal seam,the coal wall due to the influence of stress concentration and its own gravity,the coal and gas outburst accidents most likely happen at this time.In order to prevent coal and gas outburst,the "Four steps method"the shaft uncovering coal measures are adopted and has been applied success-fully.It will provide a reference for other coal mine shaft uncovering coal.%以某矿井筒揭突出煤层为原型，利用FLAC3D软件构建计算模型，研究发现：竖井揭煤工作面下部存在“漏斗”型卸压区，卸压程度由井筒中心向四周逐渐降低。井筒四周、立井工作面前后存在应力集中区，竖井与煤层法距5 m 时，煤层两帮开始出现应力集中区，应力集中区范围为距井筒外4～6 m。当竖井掘进入煤层后，煤壁由于受应力集中、煤体自身重力的影响，此时最容易发生煤与瓦斯突出的事故。为防止煤与瓦斯突出，采取“四步法”竖井揭煤措施，并得到了成功的应用，可以为其它矿井的井筒揭煤提供借鉴。
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