CAJ | 학술논문

以颗粒流理论和PFC程序为平台,根据矩张量理论建立细观尺度上岩石声发射模拟方法.该方法可同时给出声发射事件发生的时间、空间、破裂强度等特征,再现岩石裂纹孕育、发展和贯通过程,从而揭示岩石的破坏机制.结合室内花岗岩破裂全过程声发射特性试验研究成果,通过试验和计算结果的对比分析,验证该方法的可靠性,并得到以下结论:(1)在试样峰值强度前,声发射事件次数较少、破裂强度较低,且在试样内部随机分布;从试样峰值强度起至破坏时的残余强度,声发射事件次数较多、破裂强度较高,且主要沿宏观破裂带附近分布.(2)声发射事件次数随破裂强度变化近似呈正态分布.在均值与最大破裂强度之间,声发射事件累积数随破裂强度的降低近似呈线性对数函数关系.(3)每次声发射事件所包含的微破裂数,随破裂强度的提高而增加,近似呈波尔兹曼函数关系.(4)声发射事件次数与微破裂数近似呈负指数函数关系,即包含微破裂数越少的声发射事件,其所占总数的比例越大.研究成果可弥补现有声发射试验及模拟方法的不足,并作为一种新的手段为声发射试验与现场微震监测研究所利用.
이과립류이론화PFC정서위평태,근거구장량이론건립세관척도상암석성발사모의방법.해방법가동시급출성발사사건발생적시간、공간、파렬강도등특정,재현암석렬문잉육、발전화관통과정,종이게시암석적파배궤제.결합실내화강암파렬전과정성발사특성시험연구성과,통과시험화계산결과적대비분석,험증해방법적가고성,병득도이하결론:(1)재시양봉치강도전,성발사사건차수교소、파렬강도교저,차재시양내부수궤분포;종시양봉치강도기지파배시적잔여강도,성발사사건차수교다、파렬강도교고,차주요연굉관파렬대부근분포.(2)성발사사건차수수파렬강도변화근사정정태분포.재균치여최대파렬강도지간,성발사사건루적수수파렬강도적강저근사정선성대수함수관계.(3)매차성발사사건소포함적미파렬수,수파렬강도적제고이증가,근사정파이자만함수관계.(4)성발사사건차수여미파렬수근사정부지수함수관계,즉포함미파렬수월소적성발사사건,기소점총수적비례월대.연구성과가미보현유성발사시험급모의방법적불족,병작위일충신적수단위성발사시험여현장미진감측연구소이용.
Based on the particle flow theory and particle flow code(PFC),the simulative approach of rock acoustic emission(AE) in meso-scale is established by using the moment tensor theory. This approach can simultaneously give the occurrence characteristics of AE event such as time,location and magnitude,reproduce the generation, propagation and coalescence progress of cracks,and consequently reveal the rock failure mechanism. The reliability of this approach is verified by comparing the experiment and calculation data based upon the AE characteristics test of lab granite complete failure process. Some main research results are as follows:(1) Before the peak strength,the number and magnitude of AE events are less and lower,respectively;and they are distributed randomly in the sample. From the peak strength to failure residual strength,the number and magnitude of AE events are much more and higher,respectively;and they are distributed principally along the macro fracture belt. (2) The number of AE events behaves as normal distribution with the magnitude variation. Between the mean and peak value of magnitude,the cumulative number of AE events behaves as linear log function relationship with decrease of magnitude. (3) The number of microcrack in each single AE event increases and approximatively behaves as Boltzman function relationship with increase of magnitude. (4) The number of AE events behaves as negative exponential function relationship with the number of microcrack,namely in case the kind of AE event owns less microcracks;its proportion is higher in total AE events. The research results make up the deficiencies of the existing AE test and simulation method,and can be utilized as a new approach in the research of AE test and field microseismic monitoring.