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对贴井壁环型剪切源在柱状双层弹性介质中激发的SH波场进行了理论求解 ,导出了柱面Love波频散方程 ,讨论了柱面Love波存在的条件及其区域 .通过数值计算考察了柱面Love波的频散特性和激发强度 ,发现最低阶柱面Love波具有截止频率 ,这与平面半空间双层弹性介质模型下的Love波无截止频率的特征不同 .渐近分析与数值考察都表明 ,井径r1→∞时 ,柱面Love波频散方程趋向平面双层半空间的Love波方程 ,柱面Love波的截止频率趋于零 .全波计算还显示用激发SH波来探测侵入带外原状地层的横波信息是一个十分简洁的途径 .
The SH wavefield excited by the annular circular shear source in the columnar bilayer elastic medium is theoretically solved and the dispersion equation of Love wave is deduced.The existence conditions and the region of the cylinder Love wave are discussed.According to The frequency dispersion characteristics and excitation intensity of the Love wave are investigated by numerical calculation. The results show that the Love wave of the lowest order cylinder has a cutoff frequency, which is different from the characteristic of the Love wave without cutoff frequency in the half-space elastic half-space model. Both the analysis and the numerical investigation show that for the well diameter r1 → ∞, the Love wave dispersion equation of the cylinder tends to the Love wave equation in the plane double half-space and the cut-off frequency of the cylinder Love wave tends to zero. The SH wave is a very succinct way to detect the transverse wave information that invaded the out-of-band strata.