运用速度传感器和拾振器,对40 kg TNT当量爆炸塔在15、20、25和40 kg TNT炸药爆炸加载下爆炸塔旁侧实验室所在地面、屋顶以及塔顶的振动速度进行监测分析.测试结果表明:在本实验条件下实验室地面质点振动速度峰值均小于5 cm/s,振动持续时间为5～10 s,振动频率一般高于10 Hz;屋顶的竖向振动峰值是水平向的6～7倍,即存在显著的竖向振动放大效应.小波包分析表明:地面竖向振动携带的能量是水平向振动携带能量的2. 5～4. 0倍,质点振动信号中95％以上的能量处于0～160 Hz频带,而竖向振动中 90％以上的能量集中在10～40 Hz范围.研究结果提示:6 m深隔振沟的隔振效果十分有限,在超过5 kg TNT当量的加载条件下,欲取得理想的隔振效果,应选择独立地基和隔振支座的减振设计方式.%In the present work, the vibration velocities of the ground, roof and top of the 40 kg TNT equivalent blast containment chamber resulting respectively from 15, 20, 25 and 40 kg TNT explosion were monitored using velocity sensors and geophones. The measured results showed that all of the ground velocity peaks were less than 5 cm/s, the vibration frequency was almost higher than 10 Hz and the vibration duration reached 5 to 10 s, and the vertical vibration peak of the roof was obviously enlarged by 6 to 7 times that of the horizontal ones. The wavelet packet analysis of the velocities' signal showed that the vertical vibration energy of the ground was 2. 5 to 4. 0 times that of the horizontal vibration energy, more than 95 ％ of the vibration energy mostly concentrated in the range of 0-160 Hz, while more than 90％ of the vertical vibration energy was limited in the range of 10-40 Hz. The results reveal that the attenuation effect of the vibration-isolating trench at a depth of 6 m on the blast seismic waves is imperfect, the independent base and seismic isolation bearing should be adopted if we hope to obtain an ideal attenuation effect especially when the explosive weight exceeds 5 kg TNT equivalent.
展开▼
