【摘要】 采用小波分析和快速傅立叶变换相结合的方法,对工程案例的爆破震动近、中远区的实测原始信号进行小小波分解和重构,得到重构后各子频带的时间信号及频谱,在此基础上通过Matlab语言编写程序研究爆破地震波沿各分区信号的频谱及能量分布特征。指出:爆破震动各分区的主频从大到小排序为:近区>中区>远区;随着比例距离的增加,低频带能量所占信号总能量的比例升高,高频带能量所占比例下降;频率越低的频带信号,持续时间越长;除主频所在频带外,在0～2.441 5 Hz频段(比较接近建筑物的自振频率),爆破震动信号在水平方向占有不小的能量比例,故建筑物进行结构设计时考虑水平方向的抗震尤为重要。更多还原

【Abstract】 With the methods of wavelet analysis and fast Fourier transform,actual original signals from engineering project in near,medium and far zones of blasting vibration are separately decomposed and reconstructed;and time signals and spectra of all sub-frequencybands are obtained.On this basis,distribution characteristics of spectra and energy of blasting seismic waves along all zones are studied with Matlab;and it is pointed out,that the values of dominant frequency in blasting vibration zones is in attenuation sequence: near zone,medium zone,far zone;as the scaled distance increases,low frequency bands share higher proportion of total signal energy,while high frequency bands share lower;signals in lower frequency bands have longer duration;in addition to the frequency band that the dominant frequency locates in,when the band is from 0 to 2.441 5 Hz(close to the natural frequency of the buildings),blasting vibration signals in the horizontal direction occupy an assignable proportion of the energy;and thus the aseismic construction in horizontal direction is especially important for building structure designs.更多还原