采用水泥砂浆试件模拟含裂隙岩石材料并进行单轴压缩试验,利用超声波仪检测加压过程中波形和波速随试件裂隙扩展的变化.结果表明:荷载为0 MPa时,试件内部存在微缺陷,4#和5#测点的波形出现不规则变化;荷载为1~4 MPa时,试件表面没有出现裂缝,超声波的波形趋于稳定,各测点波速随应变的增加无明显变化,只是在刚施加荷载时波速有增大现象;当试件表面出现裂隙时,2#、4#和5#测点的波形均出现不规则变化,同时波速也有所下降;在裂纹扩展阶段,波形随着裂纹的扩展而发生不规则变化,波速也随应变的增加而呈明显下降趋势;裂纹贯通整个试件后,各测点的波形发生很大异常变化,且连续性差、波形不规则,波速较低.%This paper used simulated fractured rock material with cement mortar for uniaxial compression test.The ultrasonic wave gauge is used to measure the changes of the waveform and wave velocity along with the crack expansion of test piece during the pressurization process.Results show: At load of 0 MPa,there is micro flaw inside test piece,the wave form at 4# & 5# measuring spots have irregular changes.At load of 1~4 MPa,no crack occurred on surface of test piece,the wave form of ultrasonic wave became steady,the wave velocity at all measuring spots have no obvious change with the increment of strain,the wave velocity was slightly increased when the load was first applied.When there was cracks on surface,wave form at 2#,4# and 5# measuring spots have irregular changes,in the mean time the wave velocity also declined.During crack expanding stage,the wave form is changed irregularly with the expansion of crack,and the wave velocity would decline obviously with the increment of strain;If the crack went through the whole test piece,the wave form at all measuring spots would have huge changes,with less continuity,irregular wave forms and relatively lower wave velocities.
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