【摘要】 研究3种试验条件(300℃轴压94 MPa围压75 MPa,400℃轴压125 MPa围压100 MPa,500℃轴压175 MPa围压125 MPa)下花岗岩体(200 mm×400 mm)的蠕变声发射规律。研究结果表明:(1)花岗岩300℃轴压94 MPa围压75 MPa蠕变试验,整个过程经历瞬态蠕变和稳态蠕变2个阶段,蠕变第一阶段声发射信号强于蠕变第二阶段声发射信号,稳态蠕变阶段声发射活动较弱,声发射频度稳定,强度逐渐降低;400℃轴压125 MPa围压100 MPa花岗岩蠕变试验只经历稳态蠕变阶段,蠕变声发射规律与300℃稳态蠕变阶段相似;500℃轴压175 MPa围压125MPa采集到的声发射信号微弱,无法说明蠕变过程中声发射规律。(2)高温高压蠕变试验中,随着温度升高,花岗岩内部发生不同程度塑性变形和局部塑性破坏,蠕变声发射信号减弱。更多还原

【Abstract】 The creep acoustic emission rule of granite(200 mm×400 mm) was tested under three different temperatures,axial pressures and confining pressures.The research results are as follows:(1) Under the condition of 300 ℃,axial pressure of 94 MPa and confining pressure of 75 MPa,the creep process of granite experiences transient and steady creep states.The acoustic emission in transient creep state is stronger than that in steady creep state.The acoustic emission frequentness is more steady and the intensity decreases in steady creep state.Under the condition of 400 ℃,axial pressure of 125 MPa and confining pressure of 100 MPa,the creep process of granite only experiences steady creep state and the acoustic emission is similar with steady creep state in 300 ℃.Under the condition of 500 ℃,axial pressure of 175 MPa and confining pressure of 125 MPa,the acoustic emission signal is so weak that the acoustic emission rule in creep process can t be explained.(2) In the creep test with high temperature and high pressure,the acoustic emission signal becomes weak due to partial plastic deformation and partial plastic damage inside granite with the temperature increasing.更多还原