为合理确定区段小煤柱宽度及沿空巷道支护方式,以阳泉五矿8407综放工作面为例,基于采空侧基本顶断裂力学模型及围岩极限平衡理论,理论计算了合理煤柱宽度的上下限值,采用钻孔应力监测方法,对回采过程中煤柱内部应力分布进行了实测,进而确定沿空巷道支护参数.研究结果表明:沿空掘巷小煤柱宽度合理范围为9.03～ 11.80 m,取10 m为宜,煤柱侧0～3m范围煤体发生塑形破坏、3～6m范围为弹性核区、6～10m范围靠近8409采空区承载能力弱,因而在8407回风巷掘巷期间采用锚杆+长短锚索一次支护,回采期间对煤柱帮进行3 m钻孔注浆加固二次支护,现场实测数据显示,8407回风巷沿空掘进期间围岩变形量较小,回采期间顶板、注浆加固煤柱帮、实体煤帮最大变形量分别为0.20、0.05、1.00 m,围岩变形处于可控范围,实现了综放工作面安全高效回采.%In order to determine reasonable width of small coal pillar and support method of gob-side entry driving,taking No.8407 working face of Yangquan No.5 Mine as the example,based on main roof fracture model and the ultimate balanced theory,calculated the upper and lower limit values of coal pillar,the stress distribution of coal pillar was studied during the mining period by adopting the method of borehole stress measurement.The support parameters of gob-side entry driving was also calculated.Results showed that the width of small coal pillar should be chosen between 9.03 m and 10.81 m,the optimal width of coal pillar was 10 m,the coal pillar range from 0 to 3 m was damaged,range from 3 to 6 m was elastic core area,range from 6 to 10 m close to No.8409 goaf and the carrying capacity was weak.Thus,the anchor and long and short anchor cable were used to support the roadway during the time of excavation,and then the coal pillar was reinforced by grouting of 3 m drilling during period of mining.Monitoring results confirmed that deformation of roadway changed slightly during the time of excavation,the maximum deformation of roof and grouted small coal pillar side and coal side were 0.20 m,0.05 m and 1.00 m,the deformation of surrounding rock was controllable,realized safety and efficient mining in fully-mechanized top coal caving.
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