scholarly journals Integrated Ground Penetrating Radar and Electrical Resistivity Study to Explore Such Basrah Low Resistivity Soils for Engineering Purposes, Southern Iraq

2021 ◽  
Vol 54 (2E) ◽  
pp. 104-121
Author(s):  
Emad Al-Khersan
Keyword(s):  
Ground Penetrating Radar ◽  
Silty Sand ◽  
Silty Clay ◽  
University Campus ◽  
Sand Soil ◽  
Low Resistivity ◽  
Electrical Sounding ◽  
Ground Penetrating ◽  
Silty Clay Soil ◽  
Southern Iraq

A total of 45 ground penetrating radar profiles have been conducted in Basrah City, Southern Iraq, to detect buried utilities in such soils which have not been tested before. This study tries to explore how much this technique can be useful for Basrah low resistivity soils during arid and humid seasons. In Basrah University Campus (silty clay soil) and Basrah Sport City (silty sand soil), 37 and 8 ground penetrating radar profiles were achieved inside these locations respectively. Vertical electrical sounding (Schlumberger array) and electrical profiling (Wenner array) were also used in compatibility with radar surveys side by side in all sites. Here, radargrams do not reveal much more details about the subsurface conditions because of the moisture content and soil characterizations. The actual penetrating depth of 250 and 500 MHz antennas are limited to 1.4 and 0.4 m respectively due to the soil total dissolved solids of about 6790 ppm. The tests suggest that the 250 MHz antenna is somewhat better than the 500 MHz one for detecting the shapes and depths of the buried bodies in silty clay soils during rainy or even arid periods. In Basrah Sport City (500 MHz) antenna, the radargram wave signals are not good for more than 2.5 m depth, and this antenna, rather than the 250 MHZ one is suitable for silty sand soil type.

scholarly journals Landslide investigations using the geoelectrical scanning method and ground penetrating radar: Case studies

Tehnika ◽  
2021 ◽  
Vol 76 (4) ◽  
pp. 419-425
Author(s):  
Filip Arnaut ◽  
Branislav Sretenović
Keyword(s):  
Ground Penetrating Radar ◽  
Geophysical Methods ◽  
Relevant Information ◽  
Electromagnetic Signal ◽  
Near Surface ◽  
Scanning Method ◽  
Low Resistivity ◽  
Geotechnical Investigations ◽  
Landslide Body ◽  
Ground Penetrating

Geotechnical investigations of landslides for future mitigation are a complex task. To obtain relevant information, various geophysical methods are used, with varying degrees of success. The geoelectrical scanning method, also known as Electrical Resistivity Tomography (ERT) has been successfully applied in several locations in Serbia in the las three decades. The geoelectrical scanning method was used during investigations of landslides: Umka, Lukovska banja, Tara, and Trandžament, while both geoelectrical scanning and Ground Penetrating Radar (GPR) were utilized at the Trandžament landslide. The achieved results from both methods are mutually correlated at the Trandžament landslide. Correlation of GPR data with geoelectrical scanning data was only possible since there were no nearsurface low resistivity zones in the Trandžament landslide body. Otherwise, electromagnetic signal attenuation would be high in the presence of near-surface low resistivity zones, and a quality signal would be impossible to detect at the receiving antenna.

scholarly journals Geophysical investigation of foundation failure at Medina Estate, Lagos, Southwestern Nigeria

2020 ◽  
Vol 18 ◽  
pp. 35-47
Author(s):  
M.A. Oladunjoye ◽  
K.O. Adejato ◽  
A.O. Ogunkoya
Keyword(s):  
Ground Penetrating Radar ◽  
Well Logs ◽  
Vertical Electrical Sounding ◽  
Peat Layer ◽  
Geophysical Investigation ◽  
Southwestern Nigeria ◽  
Electrical Sounding ◽  
Ground Penetrating ◽  
Low Amplitude ◽  
Foundation Failure

Integrated geophysical investigation involving Ground Penetrating Radar (GPR) and Electrical Resistivity methods were carried out at Medina Estate, Lagos southwestern Nigeria to map the subsurface lithology in order to delineate its peat stratigraphy that has been causing foundation failure in the area. Twenty-one traverses (varying from 35-880 m in length) of Ground Penetrating Radar (GPR) survey were conducted along the streets of Medina trending NE-SW and NW-SE directions using the Mala 250 MHZ bi-static shielded antenna. Thirty-six Vertical Electrical Soundings (VES) were carried out using Schlumberger electrode array at some selected points along the established traverses within the area. The GPR data were processed into radar section using Rad Explorer software. The VES data were interpreted quantitatively using the partial curve matching method and 1-D forward modeling with Win Resist Software. Available litho-logs from boreholes drilled within the area were compared with the geophysical results.  Results of the GPR survey delineated three geologic layers which include the topsoil with high amplitude, parallel to sub parallel, horizontal reflections, with thickness varying from 1 to 2 m across the entire profiles and composed of lateritic clay; peat layer with low amplitude, parallel sinuous/wavy reflections with depth of occurrence ranging from 2.0 to 8 m and clay with low amplitude, planar, horizontal, sub-parallel reflections underlying the peat layer. Vertical Electrical Sounding results revealed the presence of three geological layers which are the topsoil, peat and clay and sandy clay with layer resistivity values ranging from 20- 225 Ωm, 5 – 90 Ωm and 36 to 366 Ωm and thickness values ranging from 0.5 – 2 m, 4.0-29.0 m and infinity respectively. Borehole information confirms the occurrence of shallow peat with depth ranging from 1.5 to 9 m and clay layer with depth ranging from 9 to 21 m beneath the area. The GPR survey results correlates with the well logs acquired in the study area. Based on the correlation of the geophysical results with the well logs, the GPR gives better information about the peat layer compared to the Electrical ResistivityMethod. The information obtained from this study shows that the soils at shallow depth are organic soils which are difficult foundation materials because they exhibit very high compressibility, as such making shallow foundation impossible except some form of soil improvement is carried out. The alternative approach is the adoption of deep foundations in form of piles. Keywords: Foundation Failure, Geophysical Investigation, Ground Penetrating Radar, Vertical Electrical Sounding, Peat.

scholarly journals Application of ground penetrating radar in concrete defect detection of sluice floor

2021 ◽  
Vol 276 ◽  
pp. 02023
Author(s):  
Ye Wu ◽  
Wei Yong-xia ◽  
Xu Ming-xian ◽  
Ye Lin-xiang
Keyword(s):  
Ground Penetrating Radar ◽  
Silty Clay ◽  
Quality Inspection ◽  
Propagation Characteristics ◽  
Safe Operation ◽  
Sluice Gate ◽  
Compressive Strength Test ◽  
Concrete Quality ◽  
Ground Penetrating ◽  
Defect Investigation

The defect investigation of sluice floor is an important measure to ensure the safe operation of the sluice. due to the traditional drilling methods will cause damage to the sluice floor, and the appearance inspection and compressive strength test can not evaluate the internal defects of reinforced concrete in the sluice floor. In this paper, we apply the ground penetrating radar(GPR) to the concrete quality inspection of a sluice gate in a seawall. And we describe the layout, detection principle and data processing flow of GPR. Then we simulate the propagation characteristics of radar electromagnetic wave in the presence of twodimensional electrical anomaly bodies by finite difference method. Through analyzing the amplitude, frequency and event characteristics of reflection wave shown in the gray map of GPR profiles, we determine the dividing line between concrete and muddy silty clay, finding out the density of steel in concrete, framing the location of construction joints and suspected water-filled gaps.

scholarly journals Evaluation of ground penetrating radar and vertical electrical sounding methods to determine soil horizons and bedrock at the locality Dehtáře

2013 ◽  
Vol 8 (No. 3) ◽  
pp. 105-112 ◽  
Author(s):  
E. Nováková ◽  
M. Karous ◽  
A. Zajíček ◽  
M. Karousová
Keyword(s):  
Ground Penetrating Radar ◽  
Soil Profile ◽  
Geophysical Methods ◽  
Soil Survey ◽  
Vertical Electrical Sounding ◽  
Soil Horizons ◽  
Experimental Site ◽  
Crystalline Bedrock ◽  
Electrical Sounding ◽  
Ground Penetrating

Recently, geophysical methods have been widely used in many fields including pedology. Two of them, ground penetrating radar (GPR) and vertical electrical sounding (VES) were employed at the Dehtáře experimental site with the aim to evaluate their application in the Cambisol and Stagnosol soil types and crystalline bedrock survey in Czech conditions. These measurements were complemented by the classical soil survey using a gouge auger. As a result, interpreted soil and rock environment profiles were obtained, with the identification of boundaries of Bg, C, and R soil horizons and bedrock at various degrees of weathering. The interpretation of measurement records demonstrated suitability of the VES and GPR method application, using GPR for imaging the soil profile and the top of bedrock, while the VES method gave better results in imaging greater depths. The research demonstrated advantages of the geophysical methods such as instancy, continuous imaging, and no disturbance of the subsurface. In spite of needing classical survey data for interpretation of the results obtained by the geophysical methods, their usage can bring better quality to the soil profile imaging.

scholarly journals Evaluation of Soil Foundation by Integration of Geophysical and Geotechnical Methods at West Kom Umbo Area, Aswan, Egypt

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Hafeez THA ◽  
◽  
Bekhet M ◽  
Bakr MA ◽  
Hamdy A ◽  
...  
Keyword(s):  
Electrical Resistivity ◽  
Ground Penetrating Radar ◽  
Residential Buildings ◽  
Standard Penetration Test ◽  
Geotechnical Properties ◽  
Silty Sand ◽  
Accurate Information ◽  
Geophysical Study ◽  
Soil Foundation ◽  
Ground Penetrating

This research includes combining a geophysical study with a geotechnical study to explore different soil types in the western Kom Umbo area. First: The geophysical study, which includes Electrical Resistivity and Ground Penetrating Radar were conducted to determine the subsurface layers, and to identify “gaps and soil heterogeneity, if any.” Fifty Vertical Electrical Soundings (VESs) were made to determine the layers and the electrical resistivity of the layers. Twelve Ground Penetrating Radar profiles (GPR) have also been created to identify soil homogeneity, gaps, geotechnical properties and to identify “existing cracks or faults. Second: the geotechnical study, which includes the study of a different boreholes in all areas of the study to determine the different layers and geotechnical properties. And field tests (standard penetration test) were done and laboratory tests (such as sieves analysis). And how to determine the degree of soil quality and the ability to build on it. From the above, we can combine the results of geophysics with the results of the geotechnical study to evaluate of soil foundation and to obtain confirmed and accurate information about the nature of the soil in the study area and its homogeneity and determine the possibility of exploiting and benefiting from it in industrial facilities, large, small, residential buildings, green spaces. According to this research the study area is generally divided into two layers, the first layer consists of gravel sand which has a resistivity range from 4189 to 38033 and the second layer is sand which has a resistivity value ranging from 1224 to 9682 ohm/m. and in the present study we have achieved the next procedure on the processed GPR data, displaying 2D profiles that contain the expected anomalies. Because the study area is saturated with silty sand and gravel, part of radar waves is attenuated and the reflections from the subsurface materials are weak. Results with the 100 MHz antennae are the resistive sand, gravel is a very good GPR target, and horizontal layering and stratification are evident throughout the deposit. Engineering studies on samples which collected from different sites in the study area reveal that, the results of uniformity coefficient (Cu) ranging between 3.15 (Very uniform) to 35.56 (Non-uniform). The results of coefficient of gradation range between 0.61 (poorly graded) to 2.41 (Well graded).

REFLECTION COEFFICIENT OF AN ELECTROMAGNETIC WAVE IN CONDUCTIVE MEDIA

2018 ◽  
pp. 100-106
Author(s):  
M. S. Sudakova ◽  
M. L. Vladov ◽  
M. R. Sadurtdinov
Keyword(s):  
Reflection Coefficient ◽  
Ground Penetrating Radar ◽  
Electromagnetic Waves ◽  
Water Contamination ◽  
Survey Design ◽  
Direct And Inverse Problems ◽  
The Difference ◽  
Ground Penetrating ◽  
Ideal Dielectric

Within the ground penetrating radar bandwidth the medium is considered to be an ideal dielectric, which is not always true. Electromagnetic waves reflection coefficient conductivity dependence showed a significant role of the difference in conductivity in reflection strength. It was confirmed by physical modeling. Conductivity of geological media should be taken into account when solving direct and inverse problems, survey design planning, etc. Ground penetrating radar can be used to solve the problem of mapping of halocline or determine water contamination.

Deteksi Bentuk Objek Bawah Tanah Menggunakan Pengolahan Citra B-Scan pada Ground Penetrating Radar (GPR)

2017 ◽  
Vol 3 (1) ◽  
pp. 73-83
Author(s):  
Rahmayati Alindra ◽  
Heroe Wijanto ◽  
Koredianto Usman
Keyword(s):  
Signal Processing ◽  
Ground Penetrating Radar ◽  
Post Processing ◽  
Data Survey ◽  
Ground Penetrating

Ground Penetrating Radar (GPR) adalah salah satu jenis radar yang digunakan untuk menyelidiki kondisi di bawah permukaan tanah tanpa harus menggali dan merusak tanah. Sistem GPR terdiri atas pengirim (transmitter), yaitu antena yang terhubung ke generator sinyal dan bagian penerima (receiver), yaitu antena yang terhubung ke LNA dan ADC yang kemudian terhubung ke unit pengolahan data hasil survey serta display sebagai tampilan output-nya dan post  processing untuk alat bantu mendapatkan informasi mengenai suatu objek. GPR bekerja dengan cara memancarkan gelombang elektromagnetik ke dalam tanah dan menerima sinyal yang dipantulkan oleh objek-objek di bawah permukaan tanah. Sinyal yang diterima kemudian diolah pada bagian signal processing dengan tujuan untuk menghasilkan gambaran kondisi di bawah permukaan tanah yang dapat dengan mudah dibaca dan diinterpretasikan oleh user. Signal processing sendiri terdiri dari beberapa tahap yaitu A-Scan yang meliputi perbaikan sinyal dan pendektesian objek satu dimensi, B-Scan untuk pemrosesan data dua dimensi  dan C-Scan untuk pemrosesan data tiga dimensi. Metode yang digunakan pada pemrosesan B-Scan salah satunya adalah dengan  teknik pemrosesan citra. Dengan pemrosesan citra, data survey B-scan diolah untuk didapatkan informasi mengenai objek. Pada penelitian ini, diterapkan teori gradien garis pada pemrosesan citra B-scan untuk menentukan bentuk dua dimensi dari objek bawah tanah yaitu persegi, segitiga atau lingkaran. 

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