隧洞开挖爆破地震反应谱特征研究

Response spectrnm of blasting vibration indnced by tunnel excavation

利用地震工程中应用比较成熟的反应谱理论对隧洞开挖爆破地震进行研究.针对反应谱计算中必须输入加速度数据的问题.对实测爆破振动速度数据进行数值微分计算.并采用小波分析方法消噪得到准确、清晰的加速度时程曲线.继而将其用于反应谱计算。结合不同工程中大量的爆破振动监测资料.对隧洞开挖爆破地震反应谱进行分析。结果表明:隧洞开挖爆破地震反应谱都有一些共同的特征.反应谱曲线一般存在一个明显的峰值点.峰值对应的周期集中在几毫秒到几十毫秒的区间内。另外.在归纳、整理大量地下工程开挖爆破地震反应谱的基础上,得到了隧洞开挖爆破地震的设计反应谱。

The response spectrum theory widely applied in earthquake engineering was employed to investigate blasting seismic waves induced by tunnel excavation. After numerical differential calculating for blasting vibration velocity data, an original acceleration wave curve involving with high-frequency noises was obtained. When the high-frequency noise was cleared up by wavelet transform, an accurate and clear blasting vibration acceleration curve was obtained. And then the acceleration data were used to calculate the response spectrum of blasting vibration. Response spectrum analysis of blasting vibration induced by tunnel excavation was performed with a vast amount of monitoring data in diferent projects. The result shows that response spectrum of blasting vibration induced by tunnel excavation has some same charactors. Response spectrum curves generally have a distinct peak point..At the peak point, the period is less than 100 ms. In addition, based on coordinating and suming up a great deal of response spectrum curves induced by tunnel excavation, the design response spectrum curves were presented. This research can provide a guide for studying the blasting seismic effect.