不同保载时间实验的花岗岩声发射特性研究

发布时间：2018-04-18 00:31

本文选题：花岗岩 + 保载实验　；参考：《金属矿山》2017年11期

【摘要】：为了研究冲击地压发生前岩体处于加载或保载阶段,有突出倾向的岩体处于保载蠕变状态的问题,对花岗岩试件以每30 k N为梯度进行单轴不同时间保载实验,保载时间分别为1、3、5、10和15 min,并结合声发射进行实验研究。研究结果表明:(1)不同的保载时间对试件的强度及声发射参数有很大区别。与单轴直接加载相比,保载15 min的试件强度降低了43%;与单轴直接加载试件破坏点相比,保载15 min试件破坏时声发射撞击率提高了47%,保载15 min试件破坏时能量累积提高了53%;(2)不同保载时间,每提高相同加载梯度,保载时间越长试件的声发射撞击率越高;(3)花岗岩试件在实验过程中,保载时试件损坏或保载后刚加载试件便损坏的现象,说明保载阶段对试件的破坏有很大影响;(4)花岗岩在单轴保载压缩条件下,每个阶段产生的声发射具有不同的特征。因此,可以用花岗岩保载实验来研究岩石的微观损伤破坏,也可预测现场工程岩体的宏观断裂过程。
[Abstract]:In order to study the problem that the rock mass is in the loading or loading stage before the rock burst occurs, and the outburst rock mass is in the state of loading and creep, the uniaxial loading experiments are carried out on the granite specimen with the gradient of every 30 KN at different times.The loading time is 1 ~ 3 ~ 5 ~ 5 ~ 10 min and 15 ~ (th) min respectively, and the experimental study is carried out in combination with acoustic emission.The results show that the strength and acoustic emission parameters of the specimen vary greatly with different holding time.Compared with uniaxial direct loading, the strength of the specimen with 15 min load decreased by 43%, and compared with the failure point of the specimen loaded directly by uniaxial loading,The acoustic emission impact rate of 15 min specimens was increased by 47, and the energy accumulation of 15 min specimens was increased by 53 ~ 2) with the same loading gradient.The longer the loading time is, the higher the AE impact rate of the specimen is.The results show that the loading stage has a great influence on the failure of the specimen.) under the condition of uniaxial compression, the acoustic emission produced by each stage has different characteristics.Therefore, the granite loading experiment can be used to study the microscopic damage and failure of rock, and the macroscopic fracture process of field engineering rock mass can also be predicted.
【作者单位】：东北大学资源与土木工程学院;深部金属矿山安全开采教育部重点实验室;
【基金】：国家自然科学基金项目(编号:51674061) 中央高校基本科研业务费专项(编号:N150104007)
【分类号】：TU45

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