摘要
为更好研究深井复合顶板条件下沿空留巷围岩变形破坏机理,以淮南矿区顾桥矿1115(1)工作面轨道巷工程地质条件为研究背景,利用自行研制的两向四面不等压加载试验平台进行试验,获得了掘进、一次采动、留巷和二次采动过程中巷道顶板变形特征。基于分形几何理论对复合顶板裂隙场进行定量描述,分析了巷道在不同阶段复合顶板的裂隙动态演化特征。研究结果表明:1)复合顶板变形破坏的宏观形态为"︶"型,以中低角度离层裂隙分布为主;2)复合顶板在基本顶旋转下沉过程中,裂隙快速发育,在充填体上方出现了明显的压剪裂隙;3)复合顶板裂隙分形维数随模拟过程逐渐增加,在留巷期间由于基本顶的旋转下沉,有明显的升维现象;4)顶板分形维数可以很好表征下沉量,二者近似呈现线性关系。基于研究成果,提出针对深井复合顶板条件下沿空留巷"各阶段逐级强化"和"强化护表"的支护对策与技术方案,并进行了工程验证。
In order to research the deformation and failure mechanism of roadway surrounding rock of gob-side retaining entry with compound roof in deep mine, based on the engineering geological condi-tions of 1115（1） tailentry in Guqiao Coal Mine, the excavation period,the first mining period, roadway retaining period and the second mining period were simulated by using the self-developed physical model test system. The deformation characteristics of roadway roof were obtained. The compound roof fracture field was described based on the fractal geometry theory. The dynamic evolution characteristics of compound roof fracture field were analyzed. The results have shown that：1） The macroscopic failure type of the compound roof shows the shape of ＂︶＂ and the fractures distribute mainly in a low angle;2） The compound roof fracture develops rapidly with the rotation of the main roof and the compound roof fracture of upper filling body is obvious compression-shear fracture;3） The fractal dimension of compound osite roof increases gradually with the simulation process;4） A linear relationship between the fractal dimension and the roof subsidence is obtained. Based on research results, the support meas-ures of ＂strengthening support with mining process＂ and ＂strengthening the protection of roadway sur-rounding rock surface＂ for the gob-side retaining entry with compound roof in deep mine were proposed.
出处
《采矿与安全工程学报》
EI
CSCD
北大核心
2017年第6期1067-1074,共8页
Journal of Mining & Safety Engineering
基金
国家自然科学基金项目(51274010)
关键词
沿空留巷
复合顶板
裂隙场
分形几何
护表
gob-side retaining entry
compound roof
fracture field
fractal geometry
protection of roadway surrounding rock surface
