金属矿山岩体声发射时间序列特征的试验和模拟研究
Test and simulation study on time series characteristic of rock acoustic emission in metallic mines
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摘要: 针对金属矿山特有的地理地质条件,开展相应岩石声发射试验,确定矿区矿体围岩的时间序列特征,获得岩石破裂冒落声发射参数的危险临界值,并深入研究形成该种声发射信号的破裂机制和破坏特征.然后分别对较均质岩石试样和含有结构弱面的岩石试件进行比较试验,总结弱面裂隙影响下的岩石试件产生声发射信号的规律.利用基于离散单元法的颗粒元程序进行含裂隙岩石试样数值模拟研究,通过降低接触面刚度来模拟岩石内部的损伤,通过不同的模拟条件来研究岩石的破坏情况.研究成果将为分析损伤岩体的声发射规律开辟一条新的研究途径.Abstract: According to the specific geology conditions,the acoustic emission test was carried out on the rock to determine the time series characteristic of adjoining rock in mine.The critical acoustic emission parameters of rock breakage were analyzed and the breakage principle and characteristic of the acoustic emission signals were studied.Comparing tests were individually carried out on homogeneous specimens and specimens with cracks.Under the influence of crack,the regularity of acoustic emission signal of the specimens was generalized.Finally,the process of damage,failure and AE of rocks were simulated by Particle Flow Code which is based on the theory of Distinct Element Method according to variable strength and homogeneity.The inner impair of rock was simulated through reducing the rigidity of contact surfaces and the breakage of rock was studied by different simulation conditions.The conclusions will open a new way to study the acoustic emission regulation of impaired rock.