摘要
表面点源激发浅部波场由瑞利波主导且能量主要分布于一个波长深度,当瑞利波传播路径前方存在地下异质体时,瑞利波发生散射,在散射波的影响下振源与异质体之间的表面波场发生扰动,并且瑞利波穿过异质体能量衰减。基于这一现象,采用数值计算模拟均匀半空间异质体散射波场响应,分析不同异质体(空洞、软质体、硬质体)对表面波场的影响。研究表明,异质体区域谱密度与周围谱密度明显不同,根据谱扰动对应的偏移距预估异质体水平位置。而软质体、硬质体区域谱扰动特征较为特殊,软质体上方谱密度整体呈减弱趋势,硬质体上方谱密度整体呈增强趋势。可通过偏移距-波长谱图特征波长和谱密度预估埋深。
The shallow wave field excited by the surface point source is dominated by Rayleigh waves and the energy is mainly distributed at one wavelength depth.When there is an underground heterogeneous body in front of the Rayleigh wave propagation path,the Rayleigh waves will scatter.Under the influence of the scattered wave,the surface wave field between the source and the heterogeneous body will be disturbed,and the energy of Rayleigh waves passing through the heterogeneous body will attenuate.Based on this phenomenon,this paper uses numerical calculation to simulate the scattering wave field response of homogeneous half-space heterogeneous bodies,and analyzes the influence of different heterogeneous bodies(hollow,soft and hard)on the surface wave field.The results show that the spectral density of the region is obviously different from the surrounding spectral density,and the horizontal position of the anisoplast is estimated according to the offset corresponding to the spectral disturbance.However,the spectral disturbance characteristics of soft and hard body regions are special.The spectral density above soft body decreases,while the spectral density above hard body increases.The depth can be estimated by the characteristic wavelength and spectral density of offset-wavelength spectra.
作者
郑祥
柴华友
罗金保
陈微
Zheng Xiang;Chai Huayou;Luo Jinbao;Chen Wei(School of Faculty of Civil Engineering and Architecture,Wuhan Institute of Technology,Wuhan Hubei 430074,China)
出处
《山西建筑》
2023年第21期85-88,共4页
Shanxi Architecture
关键词
瑞利波
数值模拟
异质体
散射波
谱扰动
rayleigh wave
numerical simulation
heterogeneity
scattered waves
spectral perturbation
