Characterizing the Effects of Survey Parameters on Experimental Love Wave Multichannel Analysis of Surface Wave (MASW) Data

Autor: Siavash Mahvelati, Jonathan E. Nyquist, Joseph T. Coe
Rok vydání: 2021
Předmět:
Zdroj: Pure and Applied Geophysics. 178:2933-2952
ISSN: 1420-9136
0033-4553
DOI: 10.1007/s00024-021-02790-3
Popis: Rayleigh waves employed in engineering geophysical applications are typically generated by vertical strikes on a metallic plate that serves as a coupler between an active input source (e.g., a sledgehammer) and the ground surface. Seismic surface waves can also be generated with horizontal impacts (i.e., Love waves) using specialized coupling plates. Survey design, including the source characteristics and data acquisition parameters, can influence the acquired signals and the information derived from their analysis. Despite a growing body of research on Love wave testing, much of the basic information regarding optimal Love wave field data acquisition including source effects, near-field limitations, and receiver spacing remains unquantified. The objective of this study was to improve understanding of Love survey parameters and their effect on resolution. Rayleigh and Love waveforms were collected with multiple active seismic sources at three sites and a systematic comparison was made between the two types of waves. Also, seismic wave propagation was simulated using the code SPECFEM2D to further investigate their differences. The results revealed essential information about the role of different source and survey parameters on surface wave data. For example, the minimum source offset to avoid near-field effects was comparable for Rayleigh and Love waves (0.3–0.4 of the maximum wavelength). At closer source offset locations, Rayleigh waves were more affected by near-field effects and showed an additional 10% underestimation of phase velocities. The results from this case study provide new insights about survey design and its effects on surface wave testing.
Databáze: OpenAIRE
Externí odkaz: