摘要
为解决兴隆庄煤矿3306工作面初采阶段顶煤整体性强、冒放性差、顶煤放出难的问题,在工作面回采前实施顶煤深孔预裂爆破、开切眼顶煤与顶板截断爆破试验。深孔预裂爆破提高了顶煤裂隙发育程度,降低了顶煤破碎块度,顶煤冒放性得到增强;开切眼中的顶煤、顶板截断爆破在顶板岩层中形成裂隙自由面,促使顶板提前弯曲、断裂,缩短初次来压步距。通过上述方法,初采阶段顶煤放出率由45%提高到75%,直接顶和基本顶初垮步距分别减小40.4%和36.6%,实现了顶煤的强制冒放和初次来压前的充分放出,有效提高了综放工作面初采阶段的顶煤采出率。
In order to solve the high overall top coal strength,poor top coal falling and difficult top coal caving problems at the initial stage of No.3306 coal mining face in Xinglongzhuang Mine,before the mining operation of the coal mining face,a deep borehole pre-fracturing blasting and a breaking blasting trial of top coal and roof at the open-off cut of the coal mining face was conducted.The deep borehole pre-fracturing blasting had improved the crake development degree of the top coal and reduced the broken lump coal size of the top coal.The top coal caveability was improved.The cracking free face formed in the strata above the roof by the breaking blasting in the top coal and roof above the open-off cut could make the roof bending and breaking in advance and could reduce the step distance of the initial strata pressurization.With the above method,the top coal recovery at the initial mining stage could be improved from 45% to 75% and the initial step distance of the direction roof and the main roof could be reduced by 40.4% and 36.6% individually.Thus,with the forced caving,the top coal could be fully recovered before the initial strata pressurized and the top coal mining recovery rate at the initial mining stage of the fully mechanized top coal caving mining face could be effectively improved.
出处
《煤炭科学技术》
CAS
北大核心
2011年第10期1-4,共4页
Coal Science and Technology
基金
山东科技大学科学研究"春蕾计划"资助项目(2010AZZ121)
关键词
综放工作面
初采阶段
预裂爆破
顶煤
fully mechanized top coal caving mining face
initial mining stage
pre-fracturing blasting
top coal
