爆破动载作用下金山店铁矿松软破碎矿岩稳定性研究

发布时间：2019-06-04 06:53

【摘要】：松软破碎岩体具有松、散、软、弱等力学特性，在爆破振动作用下损伤破坏较为严重，因此对爆破荷载下软岩的损伤及爆破振动对软岩巷道的稳定性影响进行研究具有非常重要的现实意义。论文通过对金山店铁矿东区软岩区域进行调查取样，掌握了软岩区域分布情况及岩石特征。对岩样进行岩石力学实验并进行岩体质量分级，，结果表明东区的高岭土、高岭土化花岗岩、矽卡化大理岩、粉状磁铁矿等大部分矿岩处于松软、破碎等级。通过东区中深孔爆破振动监测，得到东区中深孔爆破下地震波衰减规律。在此基础上，采用爆破振动动态应力比评价方法建立爆破地震波安全评价判据，并对软岩巷道进行稳定性评价，研究表明邻近巷道受爆破振动的危害较大。采用裂纹扩展理论建立软岩区域爆破累积损伤计算模型。结合实测数据对爆破作用下东区软岩累积损伤计算分析，结果表明软岩地段的矽卡化大理岩、高岭土化花岗岩等岩体受爆破振动的影响最大，受爆破振动作用产生的损伤度增长最快，需要加强支护。通过三维数值计算和分析，研究了对软岩巷道在爆破地震波作用下的动态响应情况，结果显示爆破振动对巷道围岩产生了一定的损伤，损伤程度会随着爆破次数的增加而增大。根据软岩巷道失稳变化规律及支护机理，确定了中深孔爆破最大单次起爆药量为154Kg，设计了当总装药量大于850Kg时的起爆方式，并提出了改善原有软岩巷道支护系统的U型钢棚壁后充填注浆支护方式。通过上述研究及采取的技术方案，综合分析了金山店铁矿松软破碎矿岩在爆破动荷载作用下的稳定性，为该矿软岩区域的支护提供了依据，对同类矿山也有一定借鉴作用。
[Abstract]:The soft broken rock mass has the mechanical properties of loose, scattered, soft, weak and so on, and the damage and failure are more serious under the action of blasting vibration. Therefore, it is of great practical significance to study the damage of soft rock and the influence of blasting vibration on the stability of soft rock roadway under blasting load. Through the investigation and sampling of the soft rock area in the eastern part of Jinshandian Iron Mine, the regional distribution and rock characteristics of the soft rock are grasped in this paper. The rock mechanics experiments and rock mass quality classification of rock samples are carried out. The results show that most of the minerals such as kaolin, kaolinized granite, skarn marble, powdery magnetite and so on are in soft and broken grade. Through the vibration monitoring of medium and deep hole blasting in the east area, the attenuation law of seismic wave under medium and deep hole blasting in the east area is obtained. On this basis, the dynamic stress ratio evaluation method of blasting vibration is used to establish the safety evaluation criterion of blasting seismic wave, and the stability of soft rock roadway is evaluated. The results show that the blasting vibration of adjacent roadway is harmful. Based on the crack propagation theory, the cumulative damage calculation model of blasting in soft rock area is established. Combined with the measured data, the cumulative damage of soft rock in eastern area under blasting is calculated and analyzed. the results show that the rock mass such as skarded marble and kaolinized granite in soft rock area is most affected by blasting vibration. The damage caused by blasting vibration increases the fastest and needs to be strengthened. Through three-dimensional numerical calculation and analysis, the dynamic response of soft rock roadway under blasting seismic wave is studied. The results show that blasting vibration has caused some damage to the surrounding rock of roadway, and the damage degree will increase with the increase of blasting times. According to the instability change law and support mechanism of soft rock roadway, the maximum single initiation charge quantity of medium and deep hole blasting is determined to be 154kg, and the initiation mode is designed when the total charge quantity is larger than 850Kg. The backfilling grouting support mode of U-shaped steel shed wall is put forward to improve the original support system of soft rock roadway. Through the above research and the technical scheme adopted, the stability of soft broken rock in Jinshandian Iron Mine under blasting dynamic load is comprehensively analyzed, which provides the basis for the support of soft rock area of Jinshandian Iron Mine and has certain reference function for the same kind of mine.
【学位授予单位】：武汉科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD235

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