摘要
利用TAW-3000型伺服控制试验机和PCI-2型声发射监测系统,对干燥和饱水两种状态下的泥质粉砂岩进行了单轴压缩破裂声发射监测试验,研究了两种状态下岩石的力学与声发射特性的不同以及基于声发射为基础的损伤演化过程的区别.研究表明:饱水试件的强度、弹性模量及破坏程度均较干燥试件降低,干燥试件属于典型的脆性破坏,饱水试件则发生塑性破坏;监测到的饱水试件声发射事件率水平和峰值均较干燥试件降低,饱水试件在破坏前声发射事件率曲线出现特有的增长"沉寂区",可作为实际工程预警的前兆.推导和建立了基于相对累计声发射事件率为基础的损伤演化方程,且根据Weibull参数β的拟合值表明干燥试件内部微元强度分布集中程度和均质性均强于饱水试件,即水对泥质粉砂岩造成了一定程度的损伤.
Both of TAW-3000 servo-controlled test machine and PCI-2 acoustic emission（AE） monitor system are used during the uniaxial compressive and the AE tests on argillaceous siltstone under dry and water-saturated states. The difference of rock rupture mechanics and AE characteristics on two moisture contents has been developed, as well as the damage evolution process based on AE sign. The results show that the strength, elastic modulus and the destruction level of water-saturated specimen are lower than those in dry specimen. The dry specimen is typical of brittle fracture, while the water-saturated specimen undergoes plastic damage. AE events rate level and AE events rate peak value are lower than those in dry specimen. Before the fracture of water-saturated specimen, a unique quiet region in the growth of AE events rate curve of will appears, which could be regarded as a precursor in the practical engineering. The damage evolution equation based on the relative AE accumulative events is set up and derived. According to the fitted values of β in Weibull distribution, the degree of micro-unit strength concentrated distribution in dry specimen is stronger than those in water-saturated specimen, namely water causes a certain degree of damage to argillaceous siltstone.
出处
《辽宁工程技术大学学报（自然科学版）》
CAS
北大核心
2016年第7期705-711,共7页
Journal of Liaoning Technical University (Natural Science)
基金
国家级大学生创新创业训练计划项目(201210081001)
河北省教育厅自然科学基金项目(QN2014067)
教育部高校博士学科专项科研基金项目(20120023110023)
中央高校基本科研业务费专项资金项目(2014QZ03)
关键词
泥质粉砂岩
干燥
饱水
声发射
损伤变量
本构关系
argillaceous siltstone
dry
water-saturated
acoustic emission
damage variable
constitutive relation
