节理形貌对应力波传播影响的试验研究

Experimental Study about Influence of Joint Topography on Propagation of Stress Wave

为了研究不同节理形貌对应力波传播的影响规律,依据巴顿标准剖面线,制作3组共30个含不同节理粗糙度系数(JRC)的人工节理试样,然后基于SHPB动载试验系统对其进行不同冲击载荷的试验,比较分析不同冲击载荷下的波形图以及应力波在不同节理形貌作用下的透射率,找出JRC值和应力波透射率之间的规律。结果表明:在同一冲击气压下,随着JRC值的增加,透射应力波的波形峰值呈现逐渐下降的趋势,即试样节理面越粗糙,入射应力波穿过节理面进入输出杆的透射波信号越弱,透射能量越小;同一组具有相同JRC值的试样在不同冲击气压作用下,透射率的变化趋势大致相同,即同一组JRC值下,随着入射应力波能量的增加,节理透射率也随之增加,并呈现出很强的规律性。

In order to study the influence of different joint topography on the propagation of stress wave, according to Barton standard profile,30 artificial joint samples with different joint roughness coefficient （JRC） which are divided into 3 groups are fabricated. And then based on the SHPB dynamic load test system, the test of different impact loads is carried out and the waveforms of different joints under different loading and different impact loads are obtained with compared and analyzed. The comparison and analysis of the transmittance of the corresponding force wave under different joint surface topography is conducted to find out the rule between the JRC value and the stress wave transmission. The results show that with the in- crease of the JRC value, the wave peak of the transmitted stress wave decreases gradually under the same impact pressure, that is, the more rough the joint surface of the specimen is, the weaker transmission wave signal strength with the incident stress wave passing through the joint surface into the output bar is, the smaller transmission energy is. The same set of sam- pies with the same JRC value under the corresponding different impact loading from low to high, the tendency of the trans- missivity is approximately the same, that is ,with the same set of JRC value ,with the incident stress wave energy increases, the transmissivity of the joint has increased, and strong regularity can be explored.