【摘要】 通常情况下,同一种炸药在不同孔隙比介质中的激发效果不同,不同炸药在同一介质中的激发效果也不同。本文分别分析了几何耦合和阻抗耦合对激发效果的影响,并在此基础上,以爆炸能量利用率为准则,给出了饱和水介质中爆炸能量利用率随时间的变化曲线,并分析了多孔介质中的炸药激发效果,得到了以下结论:1在爆炸作用初期,随着不耦合系数的增大,洞壁质点速度和压力减小。然而由于其衰减速度慢,随着时间的推移,洞壁质点速度和压力有可能较耦合装药时更大。因此,在某种程度上合理的非耦合装药对于更深层的地震勘探更为有利。2在高密度、高速度的碳酸盐岩中激发,孔隙比的增加引起洞壁质点速度的增大和压力的减小。在爆炸作用初期,岩石中的能量和能量利用率随孔隙比的增加而增大,随着时间的推移,孔隙比低的介质中的能量和能量利用率增加得更快,因此需综合考虑爆炸扩腔和地震子波能量来选取激发介质。3在低密度、低速度的黄土中激发,洞壁质点速度、压力和岩石中的能量均随着孔隙比的增加而增大,随着时间的推移,孔隙比对能量和能量利用率的影响更大。以上结论对不同岩性中炸药类型的选取有一定借鉴作用。更多还原

【Abstract】 Generally,same explosive have different impacts on porous media with different porosity ratio,and different explosives also have different impacts on the same media.In this paper,the influence of geometric and impedance coupling on the excitation in porous media is respectively analyzed and the relationship of explosive energy efficiency with time are shown.The following observations were obtained through theoretical analysis and model tests:1Increasing non-coupling coefficient can result in a decrease of the particle velocity and the pressure in the early explosion,and the particle velocity and pressure may increase with time.So certain reasonable uncoupled charge may be more powerful for elastic energy generation.2When seismic waves were excited in carbonate rocks with high velocity and high density,increased porosity ratio can cause increased particle velocity and decreased pressure on hole walls.In the early explosion,energy and energy efficiency increase with porosity ratio,while those of low-porosity ratio media increase more rapidly with time.So it is necessary to have consideration on both springing and wavelet energy of the excitation media.3When seismic waves were excited in loess media with low velocity and low density,the particle velocity and pressure on hole wall increase with porosity ratio,and the porosity ratio has much more influence on energy and energy efficiency with time.The above observations can be referenced for explosives selection in different lithology.更多还原