scholarly journals Subsoil Recognition for Road Investment Supported by the Integration of Geodetic and GPR Data in the Form of a Point Cloud

2021 ◽  
Vol 13 (19) ◽  
pp. 3886 ◽  
Author(s):  
Łukasz Ortyl ◽  
Marta Gabryś
Keyword(s):  
Ground Penetrating Radar ◽  
Point Cloud ◽  
Geophysical Methods ◽  
Road Construction ◽  
Spatial Visualization ◽  
Design Stage ◽  
Quality Of Results ◽  
Structure Surface ◽  
Ground Penetrating

During road construction investments, the key issue affecting the structure’s safety is accurate subsoil recognition. Identifying subsoil variability zones or natural voids can be performed using geophysical methods, and ground-penetrating radar (GPR) is recommended for this task as it identifies the location and spatial range karst formations. This paper describes the methodology of acquisition and processing of GPR data for ground recognition for road investment. Additional subsoil research was performed after karst phenomena were identified in the investment area, formations not revealed by geological recognition from earlier studies during the pre-design stage. Mala Ramac CU II radar with a 250 MHz antenna and a Leica DS2000 with 250 and 700 MHz antennas with real-time geopositioning were used to obtain the data. Regarding GPR data postprocessing, we present a method of converting spatial visualization into a point cloud that allows for GPR and geodetic data integration and confrontation. This approach enabled us to determine the locations of control trenches, the results of which were used for material validation, which is necessary to improve the reliability of subsoil recognition. The results showed a high correlation between the recorded GPR signals and the subsoil structure. Additionally, differences in the quality of results for measurements conducted before laying supporting layers with slag and on the completed road structure surface are illustrated.

scholarly journals Ground penetrating radar detection of subsnow slush on ice-covered lakes in interior Alaska

2012 ◽  
Vol 6 (6) ◽  
pp. 1435-1443 ◽  
Author(s):  
A. Gusmeroli ◽  
G. Grosse
Keyword(s):  
Ground Penetrating Radar ◽  
Geophysical Methods ◽  
Arctic Region ◽  
Water Harvesting ◽  
Lake Ice ◽  
Wet Snow ◽  
Dry Conditions ◽  
Ground Penetrating ◽  
Ice Water

Abstract. Lakes are abundant throughout the pan-Arctic region. For many of these lakes ice cover lasts for up to two thirds of the year. The frozen cover allows human access to these lakes, which are therefore used for many subsistence and recreational activities, including water harvesting, fishing, and skiing. Safe traveling condition onto lakes may be compromised, however, when, after significant snowfall, the weight of the snow acts on the ice and causes liquid water to spill through weak spots and overflow at the snow-ice interface. Since visual detection of subsnow slush is almost impossible our understanding on overflow processes is still very limited and geophysical methods that allow water and slush detection are desirable. In this study we demonstrate that a commercially available, lightweight 1 GHz, ground penetrating radar system can detect and map extent and intensity of overflow. The strength of radar reflections from wet snow-ice interfaces are at least twice as much in strength than returns from dry snow-ice interface. The presence of overflow also affects the quality of radar returns from the base of the lake ice. During dry conditions we were able to profile ice thickness of up to 1 m, conversely, we did not retrieve any ice-water returns in areas affected by overflow.

scholarly journals Ground penetrating radar detection of subsnow liquid overflow on ice-covered lakes in interior Alaska

2012 ◽  
Vol 6 (4) ◽  
pp. 3079-3099 ◽  
Author(s):  
A. Gusmeroli ◽  
G. Grosse
Keyword(s):  
Ground Penetrating Radar ◽  
Geophysical Methods ◽  
Arctic Region ◽  
Lake Ice ◽  
Wet Snow ◽  
Dry Conditions ◽  
Ground Penetrating ◽  
Ice Water ◽  
Safe Access

Abstract. Lakes are abundant throughout the pan-Arctic region. For many of these lakes ice cover lasts for up to two thirds of the year. This frozen cover allows human access to these lakes, which are therefore used for many subsistence and recreational activities, including water harvesting, fishing, and skiing. Safe access to these lakes may be compromised, however, when, after significant snowfall, the weight of the snow acts on the ice and causes liquid water to spill through weak spots and overflow at the snow-ice interface. Since visual detection of subsnow liquid overflow (SLO) is almost impossible our understanding on SLO processes is still very limited and geophysical methods that allow SLO detection are desirable. In this study we demonstrate that a commercially available, lightweight 1GHz, ground penetrating radar system can detect and map extent and intensity of SLO. Radar returns from wet snow-ice interfaces are at least twice as much in strength than returns from dry snow-ice interface. The presence of SLO also affects the quality of radar returns from the base of the lake ice. During dry conditions we were able to profile ice thickness of up to 1 m, conversely, we did not retrieve any ice-water returns in areas affected by SLO.

Measurement of Bulk Electrical Properties Using GPR with a Variable Reflector

2018 ◽  
Vol 23 (4) ◽  
pp. 489-496
Author(s):  
J. David Redman ◽  
A. Peter Annan ◽  
Nectaria Diamanti
Keyword(s):  
Electrical Properties ◽  
Moisture Content ◽  
Ground Penetrating Radar ◽  
Arrival Time ◽  
Wood Chip ◽  
Direct Wave ◽  
Trace Data ◽  
Ground Penetrating ◽  
Prototype Instrument

Bulk electrical properties of media are important inherently for ground penetrating radar (GPR) applications and for providing a means to determine indirectly other physical properties such as moisture content. We have developed a reflector whose reflectivity can be controlled electronically. This variable reflector controlled by a GPR provides an effective method to measure bulk electrical properties of media. For sample measurements, the GPR is placed on one side of a sample and the variable reflector on the opposite side. GPR trace data are then acquired with the reflector in an on-state and in the off-state. By differencing these measurements, we improve the ability to detect the specific reflection event from the variable reflector. This process removes both the direct wave and clutter from the trace data, improving the quality of the refection event and our ability to accurately pick its arrival time and amplitude. We describe the variable reflector, a prototype instrument based on the reflector and numerical modeling performed to understand its response. We also show the results of testing applications to the measurement of wood chip moisture content and monitoring of the electrical properties of concrete during the curing process.

Effectiveness of Geophysical Methods in Calcareous Harbor Fills

2013 ◽  
Author(s):  
Horst G. Brandes
Keyword(s):  
Ground Penetrating Radar ◽  
Seismic Refraction ◽  
Geophysical Methods ◽  
Fill Material ◽  
Object Locations ◽  
Ground Penetrating

The effectiveness of electromagnetic (EM), ground penetrating radar (GPR) and seismic refraction (SR) were evaluated by surveying a shallow trench in which a number of objects of varying composition and size were buried. The trench was excavated in granular calcareous fill material. An experienced geophysical contractor was asked to provide blind predictions of object locations using each of the techniques in turn. GPR with a 400 MHz antenna was the most successful, followed by SR and EM surveying. GPR and SR were also carried out at the port of Hilo to investigate complex subsurface conditions.

Identification, investigation and classification of surface depressions and chalk dissolution features using integrated LiDAR and geophysical methods

2020 ◽  
Vol 53 (4) ◽  
pp. 620-644 ◽  
Author(s):  
Zoe Elizabeth Jeffery ◽  
Stephen Penn ◽  
David Peter Giles ◽  
Linley Hastewell
Keyword(s):  
Ground Penetrating Radar ◽  
Image Interpretation ◽  
Geophysical Methods ◽  
Integrated Approach ◽  
Study Data ◽  
Aerial Photographs ◽  
Geophysical Techniques ◽  
Karstic Features ◽  
Ground Penetrating

The chalk bedrock of the Hampshire Basin, southern England is an important aquifer and is highly susceptible to dissolution, making the development and presence of karstic features a widespread occurrence. These features are hazardous because they provide possible pathways to the underlying aquifer and therefore present potential site-specific contamination risks. There is also evidence of extensive extraction, through both mining and surface quarrying, of chalk, flint and clay over many centuries. Geophysical techniques consisting of electromagnetic (EM31) and ground-penetrating radar surveys were used to identify and characterize target features identified from desk study data. The ground-penetrating radar and EM31 interpretations allowed the classification of non-anthropogenic target features, such as diffuse buried sinkholes with disturbed and subsiding clay-rich infill and varying symmetrical and asymmetrical morphologies. We describe here the investigations of such features identified at Holme Farm, Stansted House, Hampshire. The combination of EM31 data and ground-penetrating radar profiles facilitated the identification of a palaeovalley, cavities and irregular rockhead. This investigation identified locations of aquifer contamination risk as some sinkholes have been sites for the illegal dumping of waste or the infiltration of fertilizers, leaking sewage pipes or animal waste. This potential source of contamination utilizes the sinkhole as a pathway into the highly transmissive White Chalk Subgroup of Hampshire and has caused contamination of the aquifer. We conclude that our integrated approach of geophysical techniques linked to aerial photographs and LiDAR image interpretation was highly effective in the location and characterization of dissolution structures, infilled former quarries and mining features at this site.

Exploring the Japan Cave in Taman Hutan Raya Djuanda, Bandung Using GPR

2018 ◽  
Vol 23 (3) ◽  
pp. 377-381
Author(s):  
Widodo Widodo ◽  
Azizatun Azimmah ◽  
Djoko Santoso
Keyword(s):  
Dielectric Permittivity ◽  
Ground Penetrating Radar ◽  
Field Data ◽  
Geophysical Methods ◽  
Forward Modeling ◽  
Additional Line ◽  
Reflection Amplitude ◽  
Underground Cavities ◽  
Ground Penetrating ◽  
Synthetic Models

Investigating underground cavities is vital due to their potential for subsidence and total collapse. One of the proven geophysical methods for locating underground cavities at a shallow depth is ground penetrating radar (GPR). GPR uses contrasting dielectric permittivity, resistivity, and magnetic permeability to map the subsurface. The aim of this research is to prove that GPR can be applied to detect underground cavities in the Japan Cave of Taman Hutan Raya Djuanda, in Bandung, Indonesia. Forward modeling was performed first using three representative synthetic models before field data were acquired. The data acquisition was then conducted using a 100 MHz GPR shielded antenna with three lines of 80 m and one additional line 10 m long. The result showed a region of different reflection amplitude, which was proven to be the air-filled cavities.

scholarly journals Ground Penetrating Radar investigation of depositional architecture: the São Sebastião and Marizal formations in the Cretaceous Tucano Basin (Northeastern Brazil)

2016 ◽  
Vol 46 (1) ◽  
pp. 15-27 ◽  
Author(s):  
Larissa Natsumi Tamura ◽  
Renato Paes de Almeida ◽  
Fabio Taioli ◽  
André Marconato ◽  
Liliane Janikian
Keyword(s):  
Ground Penetrating Radar ◽  
Sedimentary Environment ◽  
Geophysical Methods ◽  
Radar Data ◽  
Northeastern Brazil ◽  
Sedimentary Environments ◽  
Hydrocarbon Reservoir ◽  
Depositional Architecture ◽  
Ground Penetrating ◽  
Radar Facies

ABSTRACT: One key factor for the advance in the study of fluvial deposits is the application of geophysical methods, being the Ground Penetrating Radar one of special value. Although applied to active rivers, the method is not extensively tested on the rock record, bearing interest for hydrocarbon reservoir analogue models. The São Sebastião and Marizal formations were the subject of previous studies, which made possible the comparison of Ground Penetrating Radar survey to previous stratigraphic studies in order to identify the best combination of resolution, penetration and antenna frequency for the studied subject. Eight radar facies were identified, being six of them related to fluvial sedimentary environments, one related to eolian sedimentary environment and one radar facies interpreted as coastal sedimentary environment. The Ground Penetrating Radar data showed compatibility to sedimentary structures in the outcrops, like planar and trough cross-stratified beds. It is noted that the obtained resolution was efficient in the identification of structures up to 0.3 m using a 100 MHz antenna. In this way, the Ground Penetrating Radar survey in outcrops bears great potential for further works on fluvial depositional architecture.

scholarly journals Application Research of Ground-Penetrating Radar in the Quality Inspection of Concrete Anti-seepage Panels

2019 ◽  
Vol 136 ◽  
pp. 04032
Author(s):  
Meng Li ◽  
Changde Ren ◽  
Lei Zhao ◽  
Shijiao Luo
Keyword(s):  
Ground Penetrating Radar ◽  
Rock Foundation ◽  
Quality Inspection ◽  
Local Instability ◽  
Application Research ◽  
Safe Operation ◽  
Ground Penetrating

If the sand-free cushion of concrete anti-seepage panels of reservoir is void, it will cause local instability or even crack and collapse of the panel, which will lead to large leakage of reservoir and affect the safe operation of the project. In this paper, the ground-penetrating radar (GPR) method is used to scan the concrete panel. The results show that the quality of the panel is good overall, the distribution of rebar is uniform, and the contact between the panel and the sand-free cushion is dense. Some panels have internal voids and the contact between the cushion and the rock foundation is not dense, while no obvious hollowing is found in the sand-free cushion.

Application of Comprehensive Geological Exploration for Engineering Site Option

2011 ◽  
Vol 374-377 ◽  
pp. 2256-2260
Author(s):  
Sun Yong
Keyword(s):  
Ground Penetrating Radar ◽  
Geophysical Methods ◽  
High Density ◽  
Seismic Exploration ◽  
Accurate Analysis ◽  
Positive Role ◽  
Electrical Method ◽  
Study Results ◽  
Geological Conditions ◽  
Ground Penetrating

In the process of engineering prospective design and constructing, it is necessary to avoid the adverse impact of geological phenomena, such as fault, karst and landslide. Therefore, it’s important to choose a favorable project address by scientific and effective detection with engineering geological conditions. The main exploration method for geological conditions is the geophysical exploration, including: high density electrical method, ground penetrating Radar, seismic exploration method and so on. The discrimination result with a single geological method changes much, and it is difficult to make an accurate analysis of the geological conditions. So we should composite a variety of exploration methods. In this paper, it expounds the fundamental, the working method, data explanations of the high density electrical method and ground penetrating Radar firstly. And then it takes exploration of candidate sites of an aluminum waste disposal plant for example, the geological conditions of candidate sites are analyzed under the two geophysical methods. The study results of engineering site option have a positive role in guiding the work.

Sign in / Sign up

Export Citation Format

Share Document