作　　者： ; ; ;

机构地区： 浙江大学建筑工程学院土木工程学系

出　　处： 《浙江大学学报（工学版）》 2006年第2期272-275,共4页

摘　　要： 针对平面应变弹性波动问题,研究了自由-固定边界无限大弹性板中P-SV波的传播特性.基于特征方程式,理论上求得了截止频率,并与自由-自由边界无限大弹性板的截止频率作了比较.在短波区域,理论上求得最低区的弥散曲线分支的极限相速度为Rayleigh波的波速,而其他区的弥散曲线分支的极限相速度为剪切波的波速.通过数值计算给出了弥散曲线的前十个分支.计算结果表明,在长波区域,第二和第四分支的群速度小于零;在短波区域,只有第二分支的相速度趋近于Rayleigh波的波速. Wave propagation properties for P-SV wave in a free-fixed infinite plate in the state of plane strain problem were investigated. Based on the characteristic equation, the cutoff frequencies were obtained theoretically, and comparison between the cutoff frequencies of the free-fixed infinite plate and those of free-free infinite plate were also presented. At short wavelength region, it was obtained analytically that the phase velocity in the lowest region approaches to Rayleigh wave speed that the phase velocities in other regions and approach shear wave speed. The first ten branches of the dispersion curves were depicted graphically by the numerical calculation. Numerical results show that the group velocities of the second and fourth branches are negative at large wavelength region and only the phase velocity of the second branch approaches the Rayleigh wave speed at the short wavelength region.

关 键 词： 截止频率 弥散曲线 弹性波 各向同性板

领　　域： [理学] [理学]