深部巷道动态补强支护机理及工程应用研究

发布时间：2019-01-03 09:07

【摘要】：为了有效治理深部巷道围岩难控制的问题,有必要对深部巷道围岩应力场的时空演化规律进行深入研究。本文在现场取芯、实验室试验的基础上对深部巷道围岩应力场的时空演化规律进行了理论分析、数值模拟,由此得出巷道动态补强支护的机理,并通过工程实践对动态补强支护的效果进行了验证。理论分析结果表明,巷道一次支护过后一段时间内围岩应力峰值点不断向围岩内部转移,峰值应变一旦超过围岩的屈服应变岩体便会发生流动,破碎岩体范围不断向围岩深部波及。以信湖煤矿为例,计算得知,围岩峰值点初期转移速度较快,在第60d演化速度出现拐点,此时峰值点位置处于6.96m,此后演化速度减慢,最终在第124.8天围岩峰值点基本停止在7.21m的位置。从安全角度考虑,动态补强支护的时机确定为巷道开挖后60天。进一步研究表明,原岩应力、巷道半径、内摩擦角、围岩岩性等将对支护时机的确定产生影响。补强支护方式为锚网索注喷。运用FLAC3D数值模拟软件模拟了巷道开挖不同时间节点围岩的应力状态以及位移变化情况,结果也验证了理论分析结果的正确性；选择在第60天对巷道进行锚网索注喷支护,起到了很好的控制作用。综合理论分析以及数值模拟的研究成果,在深部巷道中进行工程应用,现场支护效果观测表明,巷道围岩得到稳定的控制,动态补强支护成功应用于工程实践。
[Abstract]:In order to effectively control the surrounding rock of deep roadway, it is necessary to study the spatial and temporal evolution of stress field in deep roadway. On the basis of field coring and laboratory tests, this paper makes a theoretical analysis and numerical simulation of the space-time evolution law of surrounding rock stress field in deep roadway, from which the mechanism of dynamic reinforcement and support of roadway is obtained. The effect of dynamic reinforcement support is verified by engineering practice. The results of theoretical analysis show that the stress peak point of surrounding rock continuously shifts to the interior of surrounding rock within a period of time after the first support of roadway, and once the peak strain exceeds the yield strain of surrounding rock, the rock mass will flow. The range of the fractured rock mass is continuously spreading to the deep surrounding rock. Taking Xinhu Coal Mine as an example, the calculation shows that the initial transfer speed of the peak point of surrounding rock is relatively fast, and the turning point appears at the 60th day, the peak point is at 6.96 m, and then the evolution velocity slows down. At the end of day 124.8, the peak point of surrounding rock basically stopped at 7.21 m. From the safety point of view, the timing of dynamic reinforcement support is 60 days after excavation. Further study shows that the stress of original rock, radius of roadway, angle of internal friction and lithology of surrounding rock will affect the timing of support. The supporting method is bolting, mesh and cable grouting. FLAC3D numerical simulation software is used to simulate the stress state and displacement change of the surrounding rock at different time points of tunnel excavation. The results also verify the correctness of the theoretical analysis results. In the 60 th day, bolting, mesh and cable injection and shotcreting are selected to support the roadway, which plays a good control role. Based on the theoretical analysis and numerical simulation, the engineering application is carried out in the deep roadway. The observation of the field support effect shows that the surrounding rock of the roadway is controlled stably, and the dynamic reinforcement support is successfully applied in the engineering practice.
【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TD353

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