摘要
基于理论分析及数值计算,研究了频率分辨率、反射波等对谱分析影响,结果表明:频率分辨率会影响相位差曲线及相位差折迭数量;与振源相对的场地沟槽反射的瑞利波或分层界面的反射体波会使测点信号功率谱估计及计算的相速度-波长曲线出现扰动。通过细化技术及干扰信号切除方法可提高相速度计算精度。在低频域相位差折迭数无法统计时,用优化分析方法可以估计可能损失折迭数或额外多余的折迭数。
Based on theoretical analysis and numerical calculation, it is shown that the wrapped phase curve and phase wrapped number in frequency domain are influenced by frequency resolution. The influences of the Rayleigh , dilatational and shear waves reflected from the boundaries on spectral analysis are also discussed .The precision of phase velocity calculation can be improved by the frequency zooming and the signal cutting techniques. When phase data are poor in lower frequency domain, the least square method can be used to rectify the error of phase velocities caused by the additional or missed phase wrapped number.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2004年第3期347-353,共7页
Rock and Soil Mechanics
关键词
表面波谱分析
相位差
相速度
频散曲线
频率分辨率
spectral analysis of surface wave (SASW)
phase difference
phase velocity
dispersion
frequency resolution
