Study of underground imaging using shear waves: the stacking method of the reflected scattered wave

Abstract

To detect buried relics and ruins at shallow depths, we proposed underground imaging using shear waves and a method based on the stacking of reflected scattered waves. In this method, point reflection is assumed. To confirm the validity of our proposed method, exploration experiments were carried out at a site in Nara National Cultural Properties Research Institute. The results from this confirm the feasibility of our proposed method.

A Comprehensive Review of Acoustic Methods for Locating Underground Pipelines

“…In this set-up, the shaker was placed on the ground surface as the acoustic source, using a specially designed platform (see Figure 12b) to achieve well coupling with the soil and to generate a compressional wave. This method is a modified work based on [103], where the CDP method was adapted to locate buried point-like objects. One modification of the compressional wave method is that a time extended signal, instead of impulses, was used to drive the shaker vibration.…”

“…Accordingly, studies have been conducted to improve imaging of underground objects, by using a high-pass filter and peak position correction of received waves [104], adopting the envelope display method [105] and the deconvolution method [106]. As reported in [103], experimental work was carried out to validate the feasibility of the proposed method.…”

“…A method proposed by Sugimote et al [103] was then modified to the compressional wave method as we introduced previously. However, the imaging results have poor resolution, as shown in Figure 13.…”

A Comprehensive Review of Acoustic Methods for Locating Underground Pipelines

“…In this set-up, the shaker was placed on the ground surface as the acoustic source, using a specially designed platform (see Figure 12b) to achieve well coupling with the soil and to generate a compressional wave. This method is a modified work based on [103], where the CDP method was adapted to locate buried point-like objects. One modification of the compressional wave method is that a time extended signal, instead of impulses, was used to drive the shaker vibration.…”

“…Accordingly, studies have been conducted to improve imaging of underground objects, by using a high-pass filter and peak position correction of received waves [104], adopting the envelope display method [105] and the deconvolution method [106]. As reported in [103], experimental work was carried out to validate the feasibility of the proposed method.…”

“…A method proposed by Sugimote et al [103] was then modified to the compressional wave method as we introduced previously. However, the imaging results have poor resolution, as shown in Figure 13.…”

A shear wave ground surface vibration technique for the detection of buried pipes

“…Whilst these methods are capable of achieving good results for targets just under the surface of the ground they are not applicable to the slightly more deeply buried targets of interest in this paper because of the rapid attenuation of the Rayleigh wave with depth. However, Sugimoto et al (2000) have adapted the time domain stacking technique for the detection of objects buried at more shallow depths. More recently, the signal stacking method has been further modified by using time extended signals, an alternative excitation method and additional signal processing techniques (Papandreou, 2011, Papandreou et al, 2009, 2011 and has been used with some success to detect concrete pipes and slabs.…”

Extremely Shallow Underground Imaging Using Scanning Laser Doppler Vibrometer

“…In our past research studies, the exploration of areas that are 30 cm underground was possible using a transverse wave. 1,2) Even so, it was impossible to explore areas that are less than 30 cm below the ground surface because of the effect of the surface wave. On the other hand, remaining land mines have become a problem all over the world.…”

A Comprehensive Review of Acoustic Methods for Locating Underground Pipelines

“…In this set-up, the shaker was placed on the ground surface as the acoustic source, using a specially designed platform (see Figure 12b) to achieve well coupling with the soil and to generate a compressional wave. This method is a modified work based on [103], where the CDP method was adapted to locate buried point-like objects. One modification of the compressional wave method is that a time extended signal, instead of impulses, was used to drive the shaker vibration.…”

“…Accordingly, studies have been conducted to improve imaging of underground objects, by using a high-pass filter and peak position correction of received waves [104], adopting the envelope display method [105] and the deconvolution method [106]. As reported in [103], experimental work was carried out to validate the feasibility of the proposed method.…”

“…A method proposed by Sugimote et al [103] was then modified to the compressional wave method as we introduced previously. However, the imaging results have poor resolution, as shown in Figure 13.…”

A shear wave ground surface vibration technique for the detection of buried pipes

“…Whilst these methods are capable of achieving good results for targets just under the surface of the ground they are not applicable to the slightly more deeply buried targets of interest in this paper because of the rapid attenuation of the Rayleigh wave with depth. However, Sugimoto et al (2000) have adapted the time domain stacking technique for the detection of objects buried at more shallow depths. More recently, the signal stacking method has been further modified by using time extended signals, an alternative excitation method and additional signal processing techniques (Papandreou, 2011, Papandreou et al, 2009, 2011 and has been used with some success to detect concrete pipes and slabs.…”

Extremely Shallow Underground Imaging Using Scanning Laser Doppler Vibrometer

“…In our past research studies, the exploration of areas that are 30 cm underground was possible using a transverse wave. 1,2) Even so, it was impossible to explore areas that are less than 30 cm below the ground surface because of the effect of the surface wave. On the other hand, remaining land mines have become a problem all over the world.…”

A Comprehensive Review of Acoustic Methods for Locating Underground Pipelines

“…In this set-up, the shaker was placed on the ground surface as the acoustic source, using a specially designed platform (see Figure 12b) to achieve well coupling with the soil and to generate a compressional wave. This method is a modified work based on [103], where the CDP method was adapted to locate buried point-like objects. One modification of the compressional wave method is that a time extended signal, instead of impulses, was used to drive the shaker vibration.…”

“…Accordingly, studies have been conducted to improve imaging of underground objects, by using a high-pass filter and peak position correction of received waves [104], adopting the envelope display method [105] and the deconvolution method [106]. As reported in [103], experimental work was carried out to validate the feasibility of the proposed method.…”

“…A method proposed by Sugimote et al [103] was then modified to the compressional wave method as we introduced previously. However, the imaging results have poor resolution, as shown in Figure 13.…”

A shear wave ground surface vibration technique for the detection of buried pipes

“…Whilst these methods are capable of achieving good results for targets just under the surface of the ground they are not applicable to the slightly more deeply buried targets of interest in this paper because of the rapid attenuation of the Rayleigh wave with depth. However, Sugimoto et al (2000) have adapted the time domain stacking technique for the detection of objects buried at more shallow depths. More recently, the signal stacking method has been further modified by using time extended signals, an alternative excitation method and additional signal processing techniques (Papandreou, 2011, Papandreou et al, 2009, 2011 and has been used with some success to detect concrete pipes and slabs.…”

Extremely Shallow Underground Imaging Using Scanning Laser Doppler Vibrometer

“…In our past research studies, the exploration of areas that are 30 cm underground was possible using a transverse wave. 1,2) Even so, it was impossible to explore areas that are less than 30 cm below the ground surface because of the effect of the surface wave. On the other hand, remaining land mines have become a problem all over the world.…”