Detecting and delineating voids and mines using new surface-wave methods in Galena, Kansas

We have applied time domain 2D full-waveform inversion (FWI) to detect a known 10 m deep wood-framed tunnel at Yuma Proving Ground, Arizona. The acquired seismic data consist of a series of 2D survey lines that are perpendicular to the long axis of the tunnel. With the use of an initial model estimated from surface wave methods, a void-detection-oriented FWI workflow was applied. A straightforward [Formula: see text] quotient masking method was used to reduce the inversion artifacts and improve confidence in identifying anomalies that possess a high [Formula: see text] ratio. Using near-surface FWI, [Formula: see text] and [Formula: see text] velocity profiles were obtained with void anomalies that are easily interpreted. The inverted velocity profiles depict the tunnel as a low-velocity anomaly at the correct location and depth. A comparison of the observed and simulated waveforms demonstrates the reliability of inverted models. Because the known tunnel has a uniform shape and for our purposes an infinite length, we apply 1D interpolation to the inverted [Formula: see text] profiles to generate a pseudo 3D (2.5D) volume. Based on this research, we conclude the following: (1) FWI is effective in near-surface tunnel detection when high resolution is necessary. (2) Surface-wave methods can provide accurate initial S-wave velocity [Formula: see text] models for near-surface 2D FWI.

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Relationship between Shear Wave Velocity and SPT-N Value for Residual Soils

MATEC Web of Conferences ◽

10.1051/matecconf/201820304009 ◽

2018 ◽

Vol 203 ◽

pp. 04009

Author(s):

Nor Faizah Bawadi ◽

Nur Jihan Syamimi Jafri ◽

Ahmad Faizal Mansor ◽

Mohd Asri Ab Rahim

Keyword(s):

Surface Wave ◽

Shear Wave ◽

Wave Velocity ◽

Shear Wave Velocity ◽

Soil Profile ◽

Dynamic Parameter ◽

Kuala Lumpur ◽

Residual Soils ◽

Standard Penetration Testing ◽

Wave Methods

The shear wave velocity (Vs) is an important dynamic parameter in the field of geotechnical engineering. One of the surface wave methods is Spectral Analysis of Surface Wave (SASW) has received attention in obtaining the shear wave velocity (Vs) profile by analysing the dispersion curve. SASW is a non-destructive test, fast and time-effective for field survey. Thus, this paper proposed the application of SASW method to obtain the shear wave velocity (Vs) to represent the soil profile. This paper aims to determine the shear wave velocity (Vs) profile using SASW method, where the testing has been conducted at three site of residual soils located in Damansara, Kuala Lumpur and Nilai area. In this study, it shows that the soil profile obtained from shear wave velocity value is similar pattern with profile that obtained using Standard Penetration Testing (SPT), which conventional used in field. The shear wave velocity are proportionally increase with depth.

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Ultrasonic Longitudinal and Surface Wave Methods for

Nontraditional Methods of Sensing Stress, Strain, and Damage in Materials and Structures ◽

10.1520/stp11899s ◽

2009 ◽

pp. 173-173-14

Author(s):

DJ Buchanan ◽

R John ◽

DA Stubbs ◽

DM Benson ◽

P Karpur

Keyword(s):

Surface Wave ◽

Wave Methods

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Precision of V30 values derived from noninvasive surface wave methods at 31 sites in California

Soil Dynamics and Earthquake Engineering ◽

10.1016/j.soildyn.2019.105802 ◽

2019 ◽

Vol 127 ◽

pp. 105802

Author(s):

Yong Alan ◽

Martin Antony ◽

Boatwright John

Keyword(s):

Surface Wave ◽

Wave Methods

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Overview of surface wave methods

Surface Wave Methods for Near-Surface Site Characterization ◽

10.1201/b17268-2 ◽

2014 ◽

pp. 1-36

Keyword(s):

Surface Wave ◽

Wave Methods

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Seismic Surface Wave Methods

Field Geophysics ◽

10.1002/9780470972311.ch14 ◽

2011 ◽

pp. 261-272

Keyword(s):

Surface Wave ◽

Wave Methods

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The Passive Surface Wave Methods for Shallow Engineering Exploration Based on the ESPAC Technology

E3S Web of Conferences ◽

10.1051/e3sconf/201913101041 ◽

2019 ◽

Vol 131 ◽

pp. 01041

Author(s):

Tong Wu ◽

Kezhu Song ◽

Zhengyang Sun ◽

Hongwei Zhao ◽

Xin Hu

Keyword(s):

Surface Wave ◽

Phase Velocity ◽

Velocity Dispersion ◽

Vertical Component ◽

Original Data ◽

Phase Velocity Dispersion ◽

Wave Phase Velocity ◽

Wave Methods ◽

Rayleigh Wave Phase Velocity ◽

Selection Of

ESPAC method is a rapidly emerging field of seismological research, which can reflect the physical properties of the Earth’s medium. In the process of using the ESPAC method, sometimes the noise of the original data is relatively large, and the raw data of each seismometer needs to be preprocessed, including operations such as de-averaging, de-trending, re-sampling, normalization, and filtering. The selection of the normalized method and the selection of the bandwidth of the filter are particularly important, and it will produce the wrong result if not handled properly. This article attempts to use the extended spatial autocorrelation (ESPAC) method to extract Rayleigh-wave phase velocity dispersion curves from the vertical component of the seismic stations’ microtremors, and proposes feasible and effective solutions to the selection of the normalized method and bandwidth of bandpass filtering.

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Pseudo-linear-array analysis of passive surface waves based on beamforming

Geophysical Journal International ◽

10.1093/gji/ggaa024 ◽

2020 ◽

Vol 221 (1) ◽

pp. 640-650

Author(s):

Ya Liu ◽

Jianghai Xia ◽

Feng Cheng ◽

Chaoqiang Xi ◽

Chao Shen ◽

...

Keyword(s):

Surface Wave ◽

Surface Waves ◽

Urban Areas ◽

High Efficiency ◽

Linear Array ◽

Array Analysis ◽

Noise Sources ◽

Set Up ◽

Wave Methods ◽

Short Time

SUMMARY Linear arrays are usually deployed for passive surface-wave investigations because of their high efficiency and convenience. In populated urban areas, it is almost impossible to set up a 2-D array in terms of the restriction from the existing infrastructures. The limited azimuthal coverage, however, lacks the ability to attenuate velocity overestimation caused by directional noise sources. We came up with a novel idea to compensate the azimuthal coverage by adding two more offline receivers to a conventional linear array, which is called pseudo-linear-array analysis of passive surface waves (PLAS). We used a beamforming algorithm to capture noise sources distribution and extract accurate dispersion curves. We used array response function to explain the superiority of the pseudo-linear array over the linear array and present the basic workflow of PLAS. Synthetic tests and field examples demonstrated the feasibility of PLAS to measure unbiased dispersion image. Comparison with mostly used passive surface wave methods (refraction microtremor, multichannel analysis of passive surface waves, spatial autocorrelation method, frequency–wavenumber analysis) suggested that PLAS can serve as an alternative passive surface wave method, especially in urban areas with restricted land accessibility and short-time acquisition demands.

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