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1

Charakterystyka technologii georadarowej i możliwe kierunki jej doskonalenia

Wutke M.

Drogownictwo

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2018

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nr 9

276--280

PL

Technologia georadarowa (GPR) jest powszechnie stosowana do obrazowania obszarów podpowierzchniowych m.in. nawierzchni drogowych. Jest to metoda nieniszcząca, wykorzystująca do wykrywania sygnałów odbitych od konstrukcji podpowierzchniowych promieniowanie elektromagnetyczne w paśmie mikrofalowym. GPR transmituje do ziemi fale elektromagnetyczne, a gdy te uderzą w zakopany obiekt lub granicę materiałów o różnych stałych dielektrycznych, antena odbiorcza rejestruje zmiany w sygnale zwrotnym. Ważne jest, aby mieć podstawową wiedzę na temat działania georadaru, ponieważ jego możliwości, ale i ograniczenia są bezpośrednio skorelowane z nauką. W artykule charakteryzowano technologię georadarową ze zwróceniem szczególnej uwagi na ograniczenia stosowania metodologii. Opisuje możliwości zwiększenia efektywności pomiarów georadarowych i nowe obszary zastosowań.

EN

Ground Penetrating Radar (GPR) technology is widely used for imaging the subsurface areas, including road structures. It is a non-destructive method that uses electromagnetic waves to detect signals reflected from sub-surface constructions. GPR transmits electromagnetic waves to the ground, and when these hit a buried object or boundary of materials with different dielectric parameters, the receiving antenna registers changes in the reflected signal. It is important to have a basic knowledge related to the operation of GPR, because its capabilities, but also limitations are directly correlated with science. The article describes GPR technology with particular attention to the limitations of the methodology. It describes the possibilities of increasing the GPR efficiency and new areas of applications.

2

ERT i GPR – geofizyczne metody badań podłoża wykorzystywane w budownictwie liniowym

Maślakowski M., Józefiak K., Brzeziński K., Superczyńska M.

Przegląd Geologiczny

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2017

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Vol. 65, nr 10/2

765--771

EN

Correct determination of subgrade layers and properties is fundamental for later design and construction stages. Results obtained using traditional geotechnical tests are always of an overly specific nature - information is only provided in certain points in the field. Number of test points and the accuracy of results’ interpretation among them influence the design of an engineering structure foundation, which greatly impacts the cost of a project. Also, the lack of soil testing or insufficient investigation of soil conditions can be the reason for all kinds of legal claims from contractors which often exceed the whole investment budget by several or even several dozen percent. In order to prevent that situation new directives for geotechnical testing include additional geophysical methods such as electrical resistivity tomography (ERT) and ground penetrating radar (GPR). These non-invasive methods can give a spatial image and thus improve the accuracy of soil strata identification. However, these methods have also disadvantages and inaccuracies related to the measurement principles and interpretation of the results. This paper presents limitations and possible errors of geophysical methods ERT and GPR based on example tests carried out for road and railway engineering structures.

3

Search for Chelyabinsk Meteorite Fragments in Chebarkul Lake Bottom (GPR and Magnetic Data)

Buzin V., Edemsky D., Gudoshnikov S., Kopeikin V., Morozov P., Popov A., Prokopovich I., Skomarovsky V., Melnik N., Berkut A., Merkulov S., Vorovsky P., Bogolyubov L.

Journal of Telecommunications and Information Technology

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2017

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nr 3

69--78

EN

The paper summarizes experimental efforts of the Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation (IZMIRAN) undertaken in search of the biggest part of Chelyabinsk meteorite in the bottom of lake Chebarkul, South Ural, Russia, and to estimate the ecological effects of its subsequent excavation.

4

Multiple-ring Circular Arrayfor Ground-Penetrating Radar Applications : Basic Ideas and Preliminary Results

Vescovo R., Pajewski L.

Journal of Telecommunications and Information Technology

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2017

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nr 3

25--29

EN

In this paper, the possibility of using a multiple-ring circular array as an antenna array for Ground-Pene-trating Radar systems is investigated. The theory behind theproposed idea is presented. The preliminary numerical re-sults that are obtained suggest that the proposed congura-tion is promising. It allows achieving a wide frequency bandand low dynamic range ratio of excitations, thus simplifyingthe feeding network. Further interesting requirements maybe satised by exploiting a combination of deterministic andstochastic synthesis techniques to design the array.

5

Improving the GPR Detectability Using a Novel Loop Bowtie Antenna

Ajith K. K., Bhattacharya A.

Journal of Telecommunications and Information Technology

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2017

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nr 3

9--16

EN

The Ground Penetrating Radar (GPR) technique finds immense applications in civil engineering today, as the most suitable approach for non-destructive testing of pavements, highways, concrete structures, and more. The major challenge in carrying out a GPR evaluation is that the properties of the probed medium are usually unknown. The permittivity and conductivity of the medium may vary from those of air to water. The electromagnetic waves also have a frequency dependent attenuation. The ability of GPR to detect signals reflected and scattered by the targets largely depends upon the antenna performance. This paper studies a novel 11:1 wideband loop bowtie antenna with very good radiation properties in the entire operating bandwidth. Synthetic and experimental results are presented for the return loss and gain of the antenna. Furthermore, experimental results are presented for the radiation patterns in the E- and H-plane. We also used the antenna to measure B-scans over two different pipes, a bamboo, and a reinforced concrete structure. All results obtained with the proposed antenna have been compared with results obtained by using a RC loaded antenna. It has been found that the loop bowtie antenna has excellent detection capability and produces less clutter. The loop loading technique can be applied to existing antennas for improved GPR imaging. This will improve the detectability of GPR by improving the target return signal.

6

Analytical Investigation on a New Approach for Achieving Deep Penetration in a Lossy Medium: The Lossy Prism

Frezza F., Simeoni P., Tedeschi N.

Journal of Telecommunications and Information Technology

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2017

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nr 3

17--24

EN

Recent studies highlighted deep-penetration prop-erties of inhomogeneous waves at the interface between a loss-less and a lossy medium. Such waves can be generated bymeans of radiating structures known as Leaky-Wave Anten-nas (LWAs). Here, a different approach is proposed basedon the use of a lossy prism capable to generate an inhomo-geneous wave when illuminated by a homogeneous wave. Thelossy prism is conceived and designed thinking of Ground-Penetrating Radar (GPR). The results achieved by the lossyprism will be compared with those obtained by means of a pre-viously designed LWA that was created with the identical ob-jective. The approach of this paper is purely theoretical, andit aims at providing basic ideas and preliminary results usefulfor an innovative LWA design.

7

Advanced Inversion Techniques for Ground Penetrating Radar

Fedeli A., Pastorino M., Randazzo A.

Journal of Telecommunications and Information Technology

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2017

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nr 3

37--42

EN

Ground Penetrating Radar (GPR) systems arenowadays standard inspection tools in several application areas, such as subsurface prospecting, civil engineering and cultural heritage monitoring. Usually, the raw output of GPR isprovided as a B-scan, which has to be further processed inorder to extract the needed information about the inspectedscene. In this framework, inversescattering-based approachesare gaining an ever-increasing interest, thanks to their capabilities of directly providing images of the physical and dielectricproperties of the investigated areas. In this paper, some advances in the development of such inversion techniques in theGPR field are revised and discussed.

8

Quaternary fault activity in the SW Pannonian Basin : GPR surveying in the Bilogora Mt. (NE Croatia)

Matoš B., Zajc M., Kordić B., Tomljenović B., Gosar A.

Geological Quarterly

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2017

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Vol. 61, No. 1

19--38

EN

In areas experiencing low deformation rates, landscapes provide limited evidence of ongoing tectonic activity, being either masked or altered by exogenic processes. Accordingly, the identification of fault activity and near surface deformation is commonly accomplished by multidisciplinary research combining geological, geophysical and geomorphic methods. In this study, Quaternary fault activity in the SW Pannonian Basin is investigated in the region of Bilogora, NE Croatia. The study area is positioned along the SW margin of the Drava Depression that was uplifted during the Pliocene and Quaternary within the Drava Depression Boundary Fault Zone. In this fault zone six GPR profiles were recorded. Reflection patterns, radar facies and truncations determined fault activity and near-surface deformation at four locations with vertical displacements of ≤1 m. At two sites, profiles did not show truncation of the shallowest reflections, however, an elevation difference of ca. 10 m between two palaeostream channels along one of the profiles suggests Quaternary uplift accommodated by a mapped fault. Considering the importance of the seismogenic potential of active faults and their correlation with the seismicity of Bilogora, this research will be followed by additional studies of near-surface strata deformation and palaeoseismological fault properties.

9

Zastosowanie metody georadarowej w diagnostyce osiadań nawierzchni drogowych na przykładzie prawobrzeżnego dojazdu do mostu na Wiśle w Kwidzynie

Klukowski M., Nitkowski A.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2016

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Vol. 25, No. 3

301--310

PL

Niniejszy artykuł przedstawia wyniki kompleksowych badań georadarowych (GPR) mających na celu opis, odtworzenie przebiegu oraz wskazanie prawdopodobnych przyczyn osiadań nawierzchni drogi DK 90. Wyznaczone przy użyciu anten typu air-coupled i ground-coupled anomalne grubości konstrukcji nawierzchni oraz charakter deformacji nawierzchni i nasypu sugerują, że obserwowane uszkodzenia związane są z obecnością w podłożu gruntów ściśliwych. Odtworzony na podstawie badań georadarowych model przebiegu deformacji jest zgodny ze znaną budową geologiczną obszaru badań.

EN

In this paper we report on the comprehensive (air-coupled and ground-coupled) Ground Penetrating Radar (GPR) approach to describe and determine mode, timing and likely source of pavement settlement of the DK 90 road. Non-destructively measured anomalous pavement thickness along with identified mode of pavement and embankment deformations points to compressibility of subgrade soils. Inferred model of deformation is consistent with geological outline of studied area.

10

Rozpoznanie budowy geologicznej podłoża obiektu ARENA w Krakowie-Czyżynach metodami geofizycznymi pod kątem występowania gruntów organicznych

Pasierb B., Nawrocki W.

Przegląd Geologiczny

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2015

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Vol. 63, nr 5

289--294

EN

Geophysical research assists in clarifying the methodology of future building work. The geological structure in terms of lithological variation of Quaternary and older formations was identified in the area of the proposed garage near the ARENAobject in Krakow. In particular, the possibility of the presence of inserts of organic soils was determined. Ground Penetrating Radar (GPR) and Electrical Resistivity Tomography (ERT) were used for more complete and comprehensive recognition of the ground. As a result of the study of the subsurface, thin interbeds of weak bearing organic soils have been found just outside the outline of the planned building. It was found that the Quaternary formations which were identified by geophysical and geotechnical methods are an appropriate ground for direct foundation of the object.

11

Rozpoznawanie budowy geologicznej złoża soli kamiennej „Mogilno I” na podstawie pomiarów georadarem otworowym – korzyści, oszczędności i bezpieczeństwo

Tadych J., Plucińska A., Drogowski J., Paribek J.

Przegląd Solny

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2014

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T. 10

5--12

PL

Złoże soli kamiennej „Mogilno I”, eksploatowane otworowo od 1986 r. przez Inowrocławskie Kopalnie Soli „Solino” S.A. od lat jest coraz lepiej rozpoznawane, stosując różnorodne metody badań. W ostatnich latach zasięg złoża i jego budowa wewnętrzna zostały doprecyzowane nowoczesnymi pomiarami georadarem otworowym. Całość dotychczasowych badań geologicznych została zweryfikowana i przedstawiona w formie modelu 3D złoża, co stanowi podstawę aktualizacji dokumentacji geologicznej złoża, podnosząc jednocześnie bezpieczeństwo eksploatacji i środowiska. Obecnie pomiary georadarem otworowym stanowią istotne narzędzie standardowego pakietu prac rozpoznawczych w IKS Solino S.A.

EN

Rock salt deposit „Mogilno I”, exploited through boreholes since 1986 by Inowrocławskie Kopalnie Soli “Solino” S.A., has been better and better explored, using diverse methods. Range and internal geological structure of a salt dome has been clarified applying modern measurements - borehole georadar (Ground Penetrating Radar – GPR). The whole of geological investigations have been verified and presented as a 3D model of a deposit, that is base of geological documentation update, increasing at the same time safety of the exploitation process and natural environment as well. Nowadays borehole georadar surveys are crucial tool at Solino's standard exploration package.

12

Examination of levee condition by means of GPR

Mydlikowski R., Beziuk G.

Studia Geotechnica et Mechanica

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2009

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Vol. 31, nr 4

49-56

EN

Levees are very important elements of hydro-protection of regions placed in the neighbourhood of rivers or water reservoirs. They are subject to influence of many destructive factors. Therefore, it is necessary to examine the condition of levees periodically. Every weakening of their structure should be debugged in order to avoid breaking of the levee and consequent risk of flood. The paper presents results of examination of levees by means of an electromagnetic geophysical method: Ground Penetrating Radar (GPR). This method enables the structure of the levee to be investigated in a fast and noninvasive way. The results of GPR measurements were compared with those obtained by means of geological sounding. All the measurements were carried out on some section of the levee of the Odra River in Wrocław, Poland.