考虑黏性效应的爆破震动区的理论分析  

Theoretical analysis of blasting vibration zone considering viscous effect

作　　者：李志文 李建春[1] 洪胜男 李海波[1] 张国凯[1,2,3] LI Zhiwen;LI Jianchun;HONG Shengnan;LI Haibo;ZHANG Guokai(State Key Lab of Geo-mechanics and Geotechnical Engineering,Wuhan Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China;University of Chinese Academy of Science,Beijing 100049,China;School of Mechanical Engineering,Nanjing University of Science and Technology,Nanjing 210094,China)

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学与工程国家重点试验室,武汉430071 [2]中国科学院大学,北京100049 [3]南京理工大学机械工程学院,南京210094

出　　处：《振动与冲击》2018年第17期107-114,共8页Journal of Vibration and Shock

基　　金：国家杰出青年基金项目(41525009);国家自然科学基金重点项目(51439008)

摘　　要：由于波阵面的几何扩散和介质的吸收作用,爆破地震波在传播过程中其幅值和频率会发生一系列的变化。为探究爆破地震波的产生和传播规律,将岩体考虑为黏弹性介质,并将爆破荷载等效地施加在震动区边界上,然后从频域求得该问题的积分解,最后对积分解进行数值计算和参数分析,结果表明:爆破荷载上升时间越短,震动区边界的振动幅值越大;爆破荷载总持续时间越长,震动区边界的振动持续时间越长,但振动幅值不受影响。在相同爆破荷载作用下,介质的弹性模量和黏性系数越小,震动区边界的振动幅值越大。爆破地震波的几何衰减分为近区衰减和远区衰减,近区衰减的速率明显大于远区衰减的速率。随着黏性系数与弹性模量的比值增大,介质对爆破地震波的吸收更明显。随爆破地震波传播距离增加其高频成分相对低频成分减少,黏性系数越大,减小的速度越快。Due to geometric diffusion of wave fronts and absorption of medium,amplitude and frequency of blasting seismic waves have a series of changes in their propagation process.In order to study generation and propagation laws of blasting seismic waves,rock mass was considered as a viscoelastic medium,blasting loads were equivalently exerted on the boundary of the vibration zone,the integral solution to the problem was obtained in frequency domain.The numerical calculation and parametric analysis were done for the integral solution.The results showed that the shorter the rise time of blasting loads,the larger the boundary vibration amplitude of the vibration zone;the longer the duration for blast loads lasting,the longer the duration for the boundary vibration lasting,but the vibration amplitude is not influenced;under the action of the same blasting loads,the smaller the medium’s elastic modulus and viscosity coefficient,the larger the boundary vibration amplitude;geometric decay of blasting seismic waves is divided into near-field attenuation and far-field attenuation,the decay rate of near field is obviously larger than that of far field;with increase in the ratio of viscous coefficient to elastic modulus,medium absorbs blasting seismic waves more obviously;with increase in the propagation distance of blasting seismic waves,their higher frequency components decrease relative to their lower frequency components,the larger the viscosity coefficient,the faster the decrease speed.

关 键 词：黏弹性介质 爆破振动 振动传播规律 振动幅值 爆破荷载 

分 类 号：TD235.1[矿业工程—矿井建设]