Evaluation of Grouting Effect Detection in Goaf

2013 ◽  
Vol 438-439 ◽  
pp. 1080-1083 ◽  
Author(s):  
Hui Ren Bai ◽  
Jing Jing Li
Keyword(s):  
Electromagnetic Wave ◽  
Ground Penetrating Radar ◽  
Filling Method ◽  
Grouting Reinforcement ◽  
Ground Penetrating ◽  
Integrated Detection

The paper mainly introduces the problem of grouting reinforcement of buildings over the old goaf, and presents to the positioning of grouting reinforcement technology in the goaf. Combined with engineering example, the paper discusses the grouting filling method to strengthening governance goaf. Three methods including drill detection, ground penetrating radar (GPR) detection and electromagnetic wave CT method are used for integrated detection.

Non-Destructive Evaluation of Reinforcing Rebar Radius by Digital Image GPR Technique

2014 ◽  
Vol 501-504 ◽  
pp. 847-851
Author(s):  
Che Way Chang ◽  
Chen Hua Lin ◽  
Shyi Lin Lee ◽  
Ping Huang Chen ◽  
Ching Cheng Jen ◽  
...  
Keyword(s):  
Electromagnetic Wave ◽  
Behavior Analysis ◽  
Physical Model ◽  
Digital Image ◽  
Ground Penetrating Radar ◽  
High Efficiency ◽  
Non Destructive Evaluation ◽  
Energy Zone ◽  
Ground Penetrating ◽  
Non Destructive

Ground Penetrating Radar (GPR) is a high efficiency technology to detect the cylindrical medium in the concretes material. The electromagnetic wave is incidental to double-rebar, and measures the reflection signal behaviors from energy zone. The results from the reflection signal of electromagnetic wave of the reinforcement concretes allow evaluating the radius of double-bar (1.6cm, 1cm). A physical model can effectively measure the radius of double-bar by the result of electromagnetic wave reflex behavior analysis. The results indicate that, this techology is capable of estimating the reinforcing double-bar radius to within 6%.

scholarly journals Imaging the structure of cave ice by ground-penetrating radar

2011 ◽  
Vol 5 (2) ◽  
pp. 329-340 ◽  
Author(s):  
H. Hausmann ◽  
M. Behm
Keyword(s):  
Electromagnetic Wave ◽  
Internal Structure ◽  
Liquid Water ◽  
Ground Penetrating Radar ◽  
Wave Speed ◽  
Liquid Water Content ◽  
Thin Layers ◽  
Ice Formation ◽  
Alpine Regions ◽  
Ground Penetrating

Abstract. Several caves in high elevated alpine regions host up to several meters thick ice. The age of the ice may exceed some hundreds or thousands of years. However, structure, formation and development of the ice are not fully understood and are subject to relatively recent investigation. The application of ground-penetrating radar (GPR) enables to determine thickness, volume, basal and internal structure of the ice and provides as such important constraints for related studies. We present results from four caves located in the Northern Calcareous Alps of Austria. We show that the ice is far from being uniform. The base has variable reflection signatures, which is related to the type and size of underlying debris. The internal structure of the cave ice is characterized by banded reflections. These reflection signatures are interpreted as thin layers of sediments and might help to understand the ice formation by representing isochrones. Overall, the relatively low electromagnetic wave speed suggests that the ice is temperate, and that a liquid water content of about 2% is distributed homogenously in the ice.

scholarly journals GPR APPLIED TO RIGID PAVEMENT FROM SANTOS DUMONT AIRPORT, RJ

2014 ◽  
Vol 32 (2) ◽  
pp. 225
Author(s):  
Welitom Rodrigues Borges ◽  
Luís Anselmo Da Silva ◽  
Luciano Soares Da Cunha ◽  
Raimundo Mariano Gomes Castelo Branco ◽  
Márcio Muniz de Farias
Keyword(s):  
Electromagnetic Wave ◽  
Ground Penetrating Radar ◽  
Rio De Janeiro ◽  
Concrete Slab ◽  
Geophysical Investigation ◽  
Rigid Pavement ◽  
Ground Penetration Radar ◽  
Speed Of Propagation ◽  
Ground Penetrating ◽  
Pavement Thickness

ABSTRACT. This paper presents the results of a research performed by using Ground Penetration Radar (GPR) to evaluate the structure of the rigid pavement ofSantos Dumont Airport in Rio de Janeiro, Brazil. The GPR data profiles were acquired with 250 and 700 MHz shielded antennas. The geophysical investigation wasperformed along of 6 profiles, totaling 1432 meters of GPR sections. For calibration of the speed of propagation of electromagnetic wave were drilled three boreholesuntil the depth of 1.8 m. The results of GPR allowed the precise delineation of reflectors related to geotechnical interfaces (pavement thickness – concrete slab andmacadam) and geological (sand/embankment soil), showing the efficiency of this method in this case study.Keywords: GPR, concrete, rigid pavement, Santos Dumont Airport. RESUMO. Este trabalho apresenta o resultado de uma pesquisa desenvolvida usando Ground Penetrating Radar (GPR) para avaliar a estrutura do pavimento rígido do pátio de manobras de aeronaves do Aeroporto Santos Dumont, no Rio de Janeiro, Brasil. Para isso foram usadas antenas blindadas com frequências de250MHz e de 700 MHz. Os dados de GPR foram adquiridos no modo common offset , ao longo de 6 perfis que totalizam 1432 metros de investigação. Para a calibração da velocidade de propagação da onda eletromagnética foram executados três furos de sondagem até a profundidade de 1,8 m. Os resultados de GPR possibilitaram odelineamento preciso de refletores relacionados a interfaces geotécnicas (espessura do pavimento – revestimento de concreto e do macadame) e geológicas (areia/aterrocom entulho), mostrando a eficiência da aplicação deste método neste estudo de caso.Palavras-chave: GPR, concreto, pavimento rígido, Aeroporto Santos Dumont.

scholarly journals Researching migration methods, entropy and energy diagram to process ground penetrating radar data

2017 ◽  
Vol 17 (4B) ◽  
pp. 167-174
Author(s):  
Van Nguyen Thanh ◽  
Thuan Van Nguyen ◽  
Trung Hoai Dang ◽  
Triet Minh Vo ◽  
Lieu Nguyen Nhu Vo
Keyword(s):  
Electromagnetic Wave ◽  
Wave Velocity ◽  
Ground Penetrating Radar ◽  
Radar Data ◽  
Maximum Energy ◽  
Velocity Estimation ◽  
Data Migration ◽  
Minimum Entropy ◽  
Energy Diagram ◽  
Ground Penetrating

Electromagnetic wave velocity is the most important parameter in processing ground penetrating radar data. Migration algorithm which heavily depends on wave velocity is used to concentrate scattered signals back to their correct locations. Depending wave velocity in urban area is not easy task by using traditional methods (i.e., common midpoint). We suggest using entropy and energy diagram as standard for achieving suitable velocity estimation. The results of one numerical model and areal data indicate that migrated section using accurate velocity has minimum entropy or maximum energy. From the interpretation, size and depth of anomalies are reliably identified.

scholarly journals Frequency components of radargrams in analyses of shallow soil cavities

2018 ◽  
Vol 7 (2.13) ◽  
pp. 127
Author(s):  
Daniliev S.M ◽  
Danilieva N.A
Keyword(s):  
Electromagnetic Wave ◽  
Ground Penetrating Radar ◽  
Large Scale ◽  
Experimental Studies ◽  
Technical Condition ◽  
Filling Material ◽  
Field Frequency ◽  
Inverse Fourier Transformation ◽  
Industrial Buildings ◽  
Ground Penetrating

The urgency of the issue being studied is determined by widespread large-scale implementation of ground penetrating radar (GPR) method within the study practice of technical state of various engineering-geological sites over a long operational period. Such buildings and structures as dams, architectural landmarks, residential and industrial buildings, temples and churches, roadways and takeoff runways may be referred to main engineering and geological sites which have been studied via ground penetrating radar method. Cracks of different length, orientation and opening, as well as cavities of various localization, being distinguished by filling material, are the main types of irregularities in the above-mentioned sites, which were being formed in the process of prolonged or improper operation. However, due to vastness of the irregularities being studied and the impossibility to include all the types of possible defects into this article, we have settled on the cavities which are the most commonly encountered in the course of practice only. This article considers the approach to analysis of the electromagnetic wave field frequency characteristics being applied during conducting ground penetrating radar studies of irregularities in the structure of engineering-geological sites on the basis of the results of electromagnetic wave fields mathematical simulation, and of the results obtained in experimental studies at real engineering-geological sites as well. There has been proposed a method based of inverse Fourier transformation for studying spectrum shift in georadargrams. The georadargram is a set of registered signals, which is obtained during even movement of the georadar along the survey line. Due to that, this article is aimed at attraction of analysis of wave electromagnetic field attributes in addition to standard methods of ground penetrating radar (GPR) data processing and interpretation, which allows to extend significantly prospect capabilities of GPR method by obtaining extra data on heterogeneous zones parameters at engineering and geological sites, and, thus, proceed from qualitative notions on technical condition of studied object to quantitative ones.  

scholarly journals Subsurface Sediment Deposits of Tanjung Berikat Coast, Bangka, Determined from GPR Interpretation

2021 ◽  
Vol 873 (1) ◽  
pp. 012019
Author(s):  
L Gustiantini ◽  
U Kamiludin ◽  
M Zulfikar ◽  
Y Noviadi ◽  
U Hernawan ◽  
...  
Keyword(s):  
Electromagnetic Wave ◽  
Ground Penetrating Radar ◽  
Coarse Sand ◽  
Process Unit ◽  
Sea Level Changes ◽  
Strong Electromagnetic Wave ◽  
Granite Intrusion ◽  
Sediment Deposits ◽  
Ground Penetrating ◽  
Sediment Deposit

Abstract Tanjung Berikat Coast in Central Bangka, is a part of the Southeast Asian tin belt. We conducted four Ground-Penetrating Radar (GPR) survey lines and 13 hand auger coring to understand sediment deposition and composition. Two similar units were determined from GPR lines BLG 01–BLG 03: Unit A at the top part, reflected by parallel and continuous reflector configuration, weak–strong electromagnetic wave. Underneath Unit A is Unit B, characterized by subparallel configuration, not continuous–chaotic, weak–medium electromagnetic wave. Unit B is absent in BLG 04. We identify another two units from BLG 04 and BLG 03, Unit C, characterized by subparallel reflector configuration, not continuous– chaotic, weak–strong electromagnetic wave. It exhibits distinctive modulating contact with Unit D. Unit D is characterized by chaotic reflector configuration, relatively stronger electromagnetic wave that might be correlated to the granite intrusion Tanjung Klabat. Sediment deposit is composed of fine–coarse sand, consisting mostly of clastic plutonic and clastic biogenic (coral and mollusk fragments), which increase downward. This indicates marine-fluvial influence, which suggests that sea-level changes strongly influence sedimentation process. Unit A from GPR is correlated to these sediment deposits, the other three units might be correlated to weathering of older insitu deposit.

scholarly journals Investigation structural settlement by Ground Penetrating Radar (Case study)

2022 ◽  
Vol 961 (1) ◽  
pp. 012037
Author(s):  
Marwan Sulayman Abdullah ◽  
Hussein Hameed Karim ◽  
Zeena Waleed Samueel
Keyword(s):  
Electromagnetic Wave ◽  
Ground Penetrating Radar ◽  
High Accuracy ◽  
Differential Settlement ◽  
Cement Injection ◽  
Before And After ◽  
Ground Penetrating ◽  
Non Destructive ◽  
Geotechnical Application

Abstract Electromagnetic wave is transferred by the GPR (ground penetrating radar), and A geotechnical application may benefit from this non-destructive test. This study is proposed to estimate the type and soil problem location that causes differential settlement of a structure (pumping station) by GPR surveying. The survey is achieved before and after the treatment by cement injection method to identify the locations that took cement injections as a full injection, partial or not at all using two types of antennas (160,450) MHz. The study also will estimate the thickness of the foundation by GPR and comparing it with actually executed. The results showed the creeping soil has occurred in some parts of the soil under the foundation, and after soil treatment, most of these parts were taken injection, and others did not. Also, it was found the relatively high accuracy of GPR for detecting the thickness of the raft foundation.

scholarly journals Ballast fouling evaluation with ground penetrating radar

2018 ◽  
Vol 211 ◽  
pp. 12004
Author(s):  
Ana Margarida Marques ◽  
Simona Fontul ◽  
André Paixão
Keyword(s):  
Electromagnetic Wave ◽  
Ground Penetrating Radar ◽  
Temporal Analysis ◽  
Railway Track ◽  
Specialized Software ◽  
Future Developments ◽  
Track Condition ◽  
Ground Penetrating ◽  
Structural Aspects

In the transport infrastructures context, the support layers have a fundamental role in the degradation of the track condition, both in structural aspects and in terms of fouling of the materials that comprise them. Particularly in the field of railway research, ballast is the key element, and its fouling leads to track deterioration. Thus, the main focus of this work is based on the evaluation of the ballast fouling using Ground Penetrating Radar (GPR). In order to determine the applicability of the method on the evaluation of railway characteristics, laboratory samples and measurements carried out in situ, on sections of two railways in operation were analysed. In both cases the different ballast fouling levels were evaluated, using specialized software for this approach (temporal analysis); and then comparing these results with results of a frequency analysis in an automatic calculation program. This paper presents the possibilities of testing with GPR equipment by analysing an electromagnetic wave, in the temporal and frequency domain for the purpose of investigating the level of degradation of a railway track. Some recommendations are also made regarding the use of this method, adding the need for future developments in an attempt to reduce the number of destructive tests still practiced nowadays.

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