The combined use of MASW and resistivity surveys for levee assessment: A case study of the Melvin Price Reach of the Wood River Levee

Linearly extended earth structures (e.g., river embankments and earth dams) require specific characterization tools to efficiently evaluate stability conditions along their relevant extensions. For this aim, geophysical surveys, both seismic and electric, are commonly used and considered complementary to geotechnical investigations. They provide imaging of parameter variations along the whole structures and not just local information in correspondence of boreholes. Improvements in these survey methodologies can further increase the application of these geophysical methods, eventually also as fast‐screening characterization tools. In this paper, the first application of a new seismo‐electric streamer, specifically designed for these aims, is presented. The developed streamer allows the contemporary acquisition of seismic and electric data while being dragged along the investigated structure. The technical solutions adopted for its construction are briefly described, and its application to the characterization of an embankment is presented. The results obtained with this new system are comparable with usually adopted investigation tools with the advantage of reduced survey time and increased efficiency.

Section: Introductionmentioning

confidence: 99%

First application of a new seismo‐electric streamer for combined resistivity and seismic measurements along linearly extended earth structures

Arato¹,

Vagnon

Comina

2022

“…Geophysical methods have previously been applied to river embankments and earth dams. The methods and objectives of previous studies were as follows: fracture detection using electrical surveys and frequency domain electromagnetic (FDEM) methods (e.g., Sentenac et al ., 2013; Nthaba et al ., 2020); animal burrow detection using electrical surveys, FDEM and ground penetrating radar methods (e.g., Borgatti et al ., 2017); leakage and internal erosion detection using time‐lapse electrical surveys (e.g., Sjödahl et al ., 2008); seepage and leakage detection using electrical surveys, FDEM and self‐potential methods (e.g., Sentenac et al ., 2018); embankment and foundation soil property estimation using electrical surveys and multi‐channel analysis of surface waves (MASW) (e.g., Hayashi et al ., 2013; Rahimi et al ., 2018); and soil moisture and water saturation monitoring using electrical surveys (e.g., Jodry et al ., 2019; Tresoldi et al ., 2019). Although electrical surveys are commonly used, most of them are 2D and time‐lapse 2D surveys.…”

Section: Introductionmentioning

confidence: 99%

“…The CR method uses capacitors as the electrodes and allows the current to flow underground from an insulating surface, such as an asphalt‐paved road. The OhmMapper (Geometrics Inc., USA) system uses the CR method with line‐antenna type electrodes and has often been used for river embankment surveys (Hayashi et al ., 2013; Rahimi et al ., 2018). Other types of CR methods have also been developed, including systems that use carpet type (Rejkjær et al ., 2021) and polyvinyl alcohol (PVA) sponge electrodes (Jinguuji and Yokota, 2021).…”

Section: Introductionmentioning

confidence: 99%

Characterization of a river embankment using a non‐destructive direct current electrical survey

Umezawa

Jinguuji

Yokota

2022

River embankments are earthen structures constructed to protect areas from flooding. If a river embankment collapses, it can cause major damage to human lives; therefore, proper inspection and evaluation are essential to determine the problem areas in river embankments, and repair them if necessary, before any damage occurs. Electrical surveys are a reliable method that has been used widely. Recently, electrical surveys have been used to inspect long structures such as river embankments, highlighting the need for developing non-destructive and less fieldwork electrical survey methods. In this study, we examined a direct current electrical exploration system using polyvinyl alcohol sponge roller electrodes, which are non-destructive and can be moved smoothly without damaging the ground surface. We conducted initial experiments on a test ground in which this new system was towed by an unmanned ground vehicle to perform an electrical survey and compared the results with those obtained using conventional methods that utilize stainless steel electrodes driven into the ground. The results indicate that the direct current electrical survey using the polyvinyl alcohol electrodes yielded almost the same results as those obtained using the stainless steel electrodes. In addition, both methods were tested on a river embankment to investigate the effectiveness of the towed direct current electrical survey. We confirmed that the towed survey method was effective by comparing the resistivity cross-sections and fieldwork required for both survey types.

“…Near-surface geophysical methods are essential tools for assessing the integrity of earthen levees and dams. Seismic surface wave methods were used in conjunction with electrical resistivity methods to evaluate a levee in the Mississippi River Valley (Rahimi et al, 2018). Geotechnical borehole data were used to investigate the relationship between seismic velocity, * E-mail: mitchell.craig@csueastbay.edu electrical resistivity and soil type in Japanese levees (Hayashi et al, 2013(Hayashi et al, , 2019.…”

Section: Introductionmentioning

confidence: 99%

Active and passive seismic surface wave methods for levee assessment in the Sacramento–San Joaquin Delta, California, USA

Craig

Hayashi²,

Kozaci³

2021

Seismic surveys were performed using a novel application of combined active and passive surface wave methods to evaluate the integrity of levees protecting islands in the Sacramento-San Joaquin Delta, California, USA, from flooding. Delta islands have been undergoing rapid subsidence during the past century due to farming practices that have led to the loss of a surficial peat layer. A large earthquake on any one of several active faults in the region could cause multiple levee failures and extensive flooding in the Delta. Surface wave surveys were carried out along the crest of levees using the active method (2D multichannel analysis of surface waves) and along the base of levees using the passive method (microtremor array method). This allowed 2D seismic S-wave velocity (V S ) profiles to be prepared for each site by combining shallow data from the active survey along the crown of the levee with deeper data from a passive survey along the toe of the levee. TheseV S profiles reveal a low-velocity peat layer beneath the levee body that was confirmed by geotechnical borehole logs. Lateral variability of the levee was evaluated using average velocity to the base of the levee versus along-levee distance.