摘要
针对综放工作面厚硬顶板初次来压步距难以确定的问题,以东周窑煤矿8301工作面为工程背景,建立厚硬基本顶的固支梁模型,运用能量法求得分布于基本顶中的水平应力,进而得到基本顶初次来压步距解析式,采用数值模拟对顶板破断特征和工作面支架工作阻力进行分析,并对不同推进距离下工作面不同位置支架工作阻力进行了现场监测。研究结果表明:相比一般综放工作面,坚硬顶板条件下工作面初次来压步距和支架工作阻力明显增加,顶板破断后对工作面形成冲击较大,矿压显现剧烈;8301工作面初次来压步距为58 m,周期来压步距为15~20 m,动载系数为1.5~1.8;基于能量法求得支架额定工作阻力为13 000 k N,而来压期间支架工作阻力为11 000 k N,是额定工作面阻力的84.6%,能够满足厚硬顶板条件下煤矿安全高效开采的要求。
It is difficult to determine the first roof weighting interval of hard roof on fully mechanized caving face. Based on the working face 8301 of Dongzhouyao coal mine,a model of two edges fixed in thick and hard roof was established by using energy method. According to the model,the horizontal stress distribution in the main roof and the analytic formula for the first roof weighting interval of the main roof were obtained. The characteristics of roof breaking and working resistance of the support were analyzed by using numerical simulation. And the working resistance of support in different positions of the working face under different advance distance was attained based on field observation. The results showed that mine pressure behaviors were more intense under the condition of thick and hard roof,with larger the first roof weighting interval and higher working resistance of support as compared to general conditions. To be specific,the first roof weighting interval was about 58 m in working face 8301,while the periodic roof weighting length ranged from 15 to 20 m. The rated working resistance of support was 13,000 k N,but the observed maximum working resistance was 11 000 k N,only 78. 7% of the rated value. It is believed that safety and efficiency of coal mining under the condition of thick and hard roof can be achieved.
出处
《矿业科学学报》
2016年第2期172-180,共9页
Journal of Mining Science and Technology
基金
国家重点基础研究发展计划(973计划)(2013CB227903)
国家自然科学基金(U1361209
51574244)
关键词
综放开采
厚硬顶板
能量法
来压步距
支架工作阻力
fully mechanized caving
thick and hard roof
energy method
weighting interval
working re sistance of support
