节理面透射模型及其隔振性能研究
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摘要
振动波入射到节理界面上,与软弱断层一样会产生波场的分解,能够起到隔振作用。根据线性变形节理的透反射规律研究发现,隔振后各点的波场可由透射P波与透射S波叠加而成,其能量分配服从Zoeppritz方程,不连续位移造成了透射波的衰减;法向刚度增加透射纵波系数会增加,而切向刚度与透射纵波无关,法向与切向刚度对透射S波均有影响,刚度增加透射S波振幅逐渐降低,逐步逼近于0;由于透射后波场相互干涉,不同波场延时不同,透射合成波与入射波相比,振幅降低,持续时间增加,波形尾段有畸变;总能量系数与节理面的刚度无关,而随入射角增加不断降低。
Like soft fault, wave field would be separated into several fields if incident wave met joint interface, vibration strength then could be decreased. According to linear deformation joint model, wave transmission and reflection rules are studied. The result indicates that wave filed after vibration isolation is superimposed by transmission P wave and transmission S wave, of which the energy follows Zeoppritz equation, discontinuous displacement at joint interface causes wave attenuation. Higher normal stiffness can make larger coefficients of transmission P wave, while there isn’t connection between tangential stiffness and transmission P wave; both normal and tangential stiffnesses affect the transmission S wave, higher stiffness can make lower amplitude of transmission S wave which approximates to 0 gradually. Due to field interference after transmission, vibration amplitude of transmission composite wave will decrease, duration time will increase, and tail section of waveform will be distorted; total energy coefficient has no connection with joint stiffness, but it decreases with the increase of incident angle.
Like soft fault, wave field would be separated into several fields if incident wave met joint interface, vibration strength then could be decreased. According to linear deformation joint model, wave transmission and reflection rules are studied. The result indicates that wave filed after vibration isolation is superimposed by transmission P wave and transmission S wave, of which the energy follows Zeoppritz equation, discontinuous displacement at joint interface causes wave attenuation. Higher normal stiffness can make larger coefficients of transmission P wave, while there isn’t connection between tangential stiffness and transmission P wave; both normal and tangential stiffnesses affect the transmission S wave, higher stiffness can make lower amplitude of transmission S wave which approximates to 0 gradually. Due to field interference after transmission, vibration amplitude of transmission composite wave will decrease, duration time will increase, and tail section of waveform will be distorted; total energy coefficient has no connection with joint stiffness, but it decreases with the increase of incident angle.
引文
[1]SCHOENBERG M.Transmission and reflection of plane wave at an elastic viscoelastic interface[J].Geophys.J.R.Astr.Soc.,1971,25:144-154.
[2]NEWMARK N M.Tests and analysis of composite beams with incomplete interaction[J].Experimental Stress Analysis Newmark,1950,9(1):75-92.
[3]MURTY G S.A theoretical model for the attenuation and dispertion of stonely waves at the loosely bonded interface of elastic half space[J].Physics of the Earth and Planetary Interiors,1975,11:65-79.
[4]MYER L R,PYRAK-NOLTE L J,COOK N G W.Effects of single fracture on seismic wave propagation[C]//Proceedings of ISRM Symposium on Rock Joints.Rotterdam:A.A.Balkema,1990,467-473.
[5]ZHAO J,CAI J G.Transmission of elastic P-waves across single fractures with a nonlinear normal deformational behavior[J].Rock Mechanics and Rock Engineering,2001,34(1):3-22.
[6]CAI J G,ZHAO J.Effects of multiple parallel fractures on apparent attenuation of stress waves in rock masses[J].International Journal of Rock Mechanics and Mining Sciences,2000,37:661-682.
[7]FRAZER L N.SH propagation in rocks with planar fractures[J].Geophysical Journal International,1995,122(1):33-62.
[8]PYRAK-NOLTE L J.Seismic visibility of fractures[D].Berkeley,CA:Department of Materials Science and Mineral Engineering,University of California,1988.
[9]PYRAK-NOLTE L J.MYER L R,COOK N G W.Anisotropy in Seismic velocities and amplitudes from multiple parallel fractures[J].Journal of Geophysical Research,1990,95(11):345-358.
[10]CHEN S G,ZHAO J.A study of UDEC modeling for blast propagation in jointed rock masses[J].International Journal of Rock Mechanics and Mining Sciences,1998,35(1):93-99.
[11]范留明,闫娜,李宁.薄弹性软弱夹层的动力响应模型[J].岩石力学与工程学报,2006,25(1):88-92.FAN Liu-ming,YAN Na,LI Ning.Dynamic response model for thin soft interlayer considering interbedded reflecting waves[J].Chinese Journal of Rock Mechanics and Engineering,2006,25(1):88-92.
[12]黄润秋,余嘉顺.软弱夹层对地震波强度影响的模拟研究[J].工程地质学报,2003,11(1):75-78.HUANG Run-qiu,YüJia-shun.Modelling of the effects of properties of a buried weak layer on seismic waves[J].Journal of Engineering Geology,2003,11(1):75-78.
[13]金峰,邵伟,张立翔,等.模拟软弱夹层的动力特性的薄层单元及其工程应用[J].工程力学,2002,19(2):36-40.JIN Feng,SHAO Wei,ZHANG Li-xiang,et al.A thin-layer element for simulation of static and dynamic characteristic of soft interlayer and its application[J].Engineering Mechanics,2002,19(2):36-40.
[14]潘纪顺,张先康,赵成斌,等.二维复杂介质中地震波走时和射线的计算方法及其应用[J].地震研究,2006,27(3):245-250.PAN Ji-xun,ZHANG Xian-kang,ZHAO Cheng-bin,et al.Computation method of seismic wave travel times and rays in 2D complicated velocity model and its application[J].Journal of Seismological Research,2006,27(3):245-250.
[15]范留明,李宁.软弱夹层的透射模型及其隔震特性研究[J].岩石力学与工程学报,2005,24(14):2457-2462.FAN Liu-ming,LI Ning.Transmission model of weak intercalation and its vibration isolation properties[J].Chinese Journal of Rock Mechanics and Engineering,2005,24(14):2457-2462.
[16]考尔斯基H.固体中的振动波[M].北京:科学出版社,1958.
[2]NEWMARK N M.Tests and analysis of composite beams with incomplete interaction[J].Experimental Stress Analysis Newmark,1950,9(1):75-92.
[3]MURTY G S.A theoretical model for the attenuation and dispertion of stonely waves at the loosely bonded interface of elastic half space[J].Physics of the Earth and Planetary Interiors,1975,11:65-79.
[4]MYER L R,PYRAK-NOLTE L J,COOK N G W.Effects of single fracture on seismic wave propagation[C]//Proceedings of ISRM Symposium on Rock Joints.Rotterdam:A.A.Balkema,1990,467-473.
[5]ZHAO J,CAI J G.Transmission of elastic P-waves across single fractures with a nonlinear normal deformational behavior[J].Rock Mechanics and Rock Engineering,2001,34(1):3-22.
[6]CAI J G,ZHAO J.Effects of multiple parallel fractures on apparent attenuation of stress waves in rock masses[J].International Journal of Rock Mechanics and Mining Sciences,2000,37:661-682.
[7]FRAZER L N.SH propagation in rocks with planar fractures[J].Geophysical Journal International,1995,122(1):33-62.
[8]PYRAK-NOLTE L J.Seismic visibility of fractures[D].Berkeley,CA:Department of Materials Science and Mineral Engineering,University of California,1988.
[9]PYRAK-NOLTE L J.MYER L R,COOK N G W.Anisotropy in Seismic velocities and amplitudes from multiple parallel fractures[J].Journal of Geophysical Research,1990,95(11):345-358.
[10]CHEN S G,ZHAO J.A study of UDEC modeling for blast propagation in jointed rock masses[J].International Journal of Rock Mechanics and Mining Sciences,1998,35(1):93-99.
[11]范留明,闫娜,李宁.薄弹性软弱夹层的动力响应模型[J].岩石力学与工程学报,2006,25(1):88-92.FAN Liu-ming,YAN Na,LI Ning.Dynamic response model for thin soft interlayer considering interbedded reflecting waves[J].Chinese Journal of Rock Mechanics and Engineering,2006,25(1):88-92.
[12]黄润秋,余嘉顺.软弱夹层对地震波强度影响的模拟研究[J].工程地质学报,2003,11(1):75-78.HUANG Run-qiu,YüJia-shun.Modelling of the effects of properties of a buried weak layer on seismic waves[J].Journal of Engineering Geology,2003,11(1):75-78.
[13]金峰,邵伟,张立翔,等.模拟软弱夹层的动力特性的薄层单元及其工程应用[J].工程力学,2002,19(2):36-40.JIN Feng,SHAO Wei,ZHANG Li-xiang,et al.A thin-layer element for simulation of static and dynamic characteristic of soft interlayer and its application[J].Engineering Mechanics,2002,19(2):36-40.
[14]潘纪顺,张先康,赵成斌,等.二维复杂介质中地震波走时和射线的计算方法及其应用[J].地震研究,2006,27(3):245-250.PAN Ji-xun,ZHANG Xian-kang,ZHAO Cheng-bin,et al.Computation method of seismic wave travel times and rays in 2D complicated velocity model and its application[J].Journal of Seismological Research,2006,27(3):245-250.
[15]范留明,李宁.软弱夹层的透射模型及其隔震特性研究[J].岩石力学与工程学报,2005,24(14):2457-2462.FAN Liu-ming,LI Ning.Transmission model of weak intercalation and its vibration isolation properties[J].Chinese Journal of Rock Mechanics and Engineering,2005,24(14):2457-2462.
[16]考尔斯基H.固体中的振动波[M].北京:科学出版社,1958.
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