【摘要】 为研究孔底空气间隔装药降低爆破振动效应的最佳空气层比例,进行了现场试验。首先基于试验数据,利用小波分析与AOK分布相结合的方法,对不同空气层比例的实测爆破地震波质点振速峰值、主频、主频持续时间、频带优势频率持续时间以及频带能量比进行了研究。结果表明:随着空气层比例的增加,爆破地震波质点振速峰值降低、主频降低、主频持续时间延长、频带优势频率持续时间延长并且频带能量比向低频发展。然后以与建筑物固有频率相接近的7.812 5~15.625 0 Hz频带能量为指标,进行了降低爆破振动效应的最佳空气层比例的选取,并结合实际工程证明了该方法的可行性与有效性。更多还原

【Abstract】 In order to study the best air-decking ratio of the hole-bottom air space charging to reduce blasting vibration effect,a field experiment was conducted.First,based on the experimental data,using wavelet decomposition combined with the AOK time-frequency representation,peak particle velocity of blasting seismic waves,dominant frequency,duration of dominant frequency,duration of preponderant frequency and frequency-band energy ratio was studied under different air-decking ratio.The results show that,with the increase of air-decking ratio,peak particle velocity of blasting seismic waves and dominant frequency are decreasing,duration of dominant frequency and duration of dominant frequency are increasing,and frequency-band energy ratio is developing toward low frequency.Then,with 7.812 5-15.625 0 Hz frequency-band energy which is closed to natural frequency of buildings as the indicator,the best air-decking ratio to reduce blasting vibration has been selected,and combined with practical work,the feasibility and effectiveness of the method were proved.更多还原