【摘要】 以福建省罗源县正在建设的龟屿隧道爆破工程为例,分析了隧道爆破地震波的传播规律和对毗邻大黄鱼育苗池的水中声场环境的影响。研究结果表明:(1)爆破作业将显著地增加毗邻大黄鱼育苗池的水中声强(比未爆破前的水中声强高约60～80dB),强度的增加与爆破药量成正比,与爆点的距离成反比,且距离的影响远大于爆破药量的影响;(2)在海水高潮和低潮的2个时段,由于爆破地震波传播途径的不同,毗邻大黄鱼育苗池的水中声场环境在强度和频率能量分布上均存在差异:育苗池中低潮时段的水中声强小于高潮时段的水中声强;低潮时段声波能量主要分布在小于400Hz的较低频带上,而高潮时段的声波能量主要分布在200～1 000Hz的较高频带上。因此,为减小隧道爆破对育苗池中大黄鱼的伤害,结合分析大黄鱼对水中声波的敏感频率(500～800Hz)及敏感强度,需降低育苗池的水中声强并使声波能量分布向低频带转移,选择在低潮时段、采用低药量进行隧道作业。更多还原

【Abstract】 Underwater sound effects generated by tunnel-explosion were studied and an observation was performed to monitor the underwater sound pressure in Pseudosciaena crocea’s breeding pond when Guiyu tunnel blast engineering occurred thither coastal harbor in Luoyuan County,Fujian Province.Based on acoustic theory of transmission and reflection on solid-fluid interface,the results show that blasting seismic wave makes impact on underwater environment through two kinds of sound transmitted paths.The underwater sound intensity increases sharply(up to 150 dB) in breeding pond when Guiyu tunnel blast engineering occurs,and the increment of sound intensity is directly proportional to the mass of explosives as well as which is inversely proportional to the distance from blasting point.However,the effect of distance is greater than that of mass.Additionally,at different time of low tide and high tide,the sound intensity generated by blasting seismic wave in pond has a significant difference due to the two paths of sound propagation in different transmitted media.With the increment of distance,sound intensity at low tide time declines more quickly than that at high tide time.Similarly,the sound energy distribution in frequency band has different shape.Sound at high tide time is dominant in frequency band of 200～1 000 Hz.On the other hand,the frequency of sound in pond at low tide time is mainly less than 400 Hz.The greater of the water depth above seabed is,the lower of the cut-off low frequency is for underwater acoustic waveguide effect.Consequently,the low tide time for Guiyu tunnel blasting should be chosen so that it can decrease the harm of high intensity in Pseudosciaena crocea’s breeding pond,avoiding to do harm to pseudosciaena crocea’s body in the sound resonant frequency of 500～800 Hz.更多还原