【摘要】 爆破振动信号分析是研究岩质边坡动力稳定性的基础和前提。希尔伯特-黄变换(HHT)由于其自适应性的特点在分析诸如爆破振动这样的非平稳随机信号中大量应用。以鲁坨路路堑边坡爆破工程为例,提取现场实测的爆破振动信号,采用HHT方法对该信号进行时频和能量分布特征分析,同时对边坡稳定性和临近建(构)筑物的安全做出相应的判定。结果表明:经验模态分解可以无需提前设定基函数,完全按照信号本身的时间尺度分解出信号的固有模态函数(IMF);对IMF分量的判断分析可以提取并过滤原始信号中的干扰成分,通过进一步降噪分解,能更好地体现原始爆破信号的时频和能量分布;Hilbert谱可以清晰地反映原始信号时间-频率-能量关系,从而对边坡稳定和临近建(构)筑物的安全提供可靠的理论指导。基于背景工程爆破信号的HHT分析,原始信号的振动能量主要分布在0~1.5 s时间段和0~50 Hz低频段,需要重点关注建(构)筑物的共振破坏现象。更多还原

【Abstract】 Blasting vibration signal analysis is the foundation and precondition to study the dynamic stability of slope. Because of the adaptability of Hilbert-Huang transform( HHT),it is widely used in analyzing non-stationary random signals,such as blasting vibration. Based on Lutuo Road blasting engineering,the blasting vibration signal is extracted,and the time-frequency and energy distribution are analyzed by HHT transform. The stability of slope and the safety of buildings are considered. Results show that it is no necessary to set a primary function in advance,and the intrinsic mode function( IMF) of signal can be resolved according to the time scale by EMD decomposition; the interference elements in the original signal can be extracted through the analysis of IMF,and the time-frequency and energy distribution of the original signal can be reflected through the noise reduction processing; Hilbert spectrum can clearly reflect the relations among energy,frequency and time,thus providing a reliable theoretical guidance forthe stability of slope and the safety of buildings. Based on the HHT transform,the energy of blasting vibration is mainly distributed in 0 ~ 1. 5 s and 0 ~ 200 Hz,especially in 0 ~ 50 Hz.更多还原