Wyniki wyszukiwania - BazTech

1

Identification of the resistive force of the tool on the basis of georadar measurements

Kiełbasa Paweł, Zagórda Mirosław, Juliszewski Tadeusz, Akinsunmade Akinniyi, Tomecka-Suchoń Sylwia, Karczewski Jerzy, Pysz Paweł

Przegląd Elektrotechniczny

|

2022

|

R. 98, nr 12

213--216

EN

In Europe, the area of soil degraded by over-compaction is estimated at 33 million hectares. The aim of the research was the potential working resistance of the tool in the soil medium based on the analysis of the GPR echogram. The scope of the research included strain gauge measurement of the tool working resistance force in the TUZ. The experiment included several ranges of tool operating depth, the limit of which was tractor drive wheel slippage exceeding 50%. The measurement of compactness was carried out in the trace of the tractor drive wheels at intervals resulting from subsoil variability; the depth of soil penetration was 0.8m. GPR scanning using the reflexive profiling method was carried out in the tractor wheel track, which was at the same time the footprint of the measurement of the working resistance force. Comparison of the obtained characteristics, i.e. working resistance force and echogram gave satisfactory results, however, it should be noted that their use is limited to a homogenous soil environment. In case of changes in the soil environment, the measuring system should be calibrated each time, so that the GPR echogram is adequate to the generated resistance force of the tool or soil compactness determined with the penetrometer. It was observed that: a) the number of passes less than four influenced only the compaction of topsoil up to the level of 0.2m, whereas with a greater number of passes this influence was also transferred to lower layers of the soil profile, b) each of the methods showed on average over 2 times increase in compactness between the profile of non-compacted soil and that of soil after eight passes by the tractor wheels.

PL

W Europie powierzchnię gleb zdegradowanych w wyniku nadmiernego zagęszczenia szacuje się na 33 mln ha. Celem badań był potencjalny opór roboczy narzędzia w ośrodku glebowym na podstawie analizy echogramu GPR. Zakres badań obejmował tensometryczny pomiar siły oporu roboczego narzędzia w TUZ. Eksperyment obejmował kilka zakresów głębokości pracy narzędzia, których granicą był poślizg kół napędowych ciągnika przekraczający 50%. Pomiar zwięzłości przeprowadzono w śladzie kół napędowych ciągnika w odstępach wynikających ze zmienności podłoża; głębokość penetracji gruntu wynosiła 0,8 m. Skanowanie georadarowe metodą profilowania refleksyjnego przeprowadzono w śladzie kół ciągnika, który był jednocześnie śladem pomiaru siły oporu roboczego. Porównanie uzyskanych charakterystyk, tj. siły oporu roboczego i echogramu dało zadowalające wyniki, jednak należy zaznaczyć, że ich zastosowanie jest ograniczone do jednorodnego środowiska gruntowego. W przypadku zmian środowiska gruntowego należy każdorazowo kalibrować układ pomiarowy, tak aby echogram GPR był adekwatny do generowanej siły oporu narzędzia lub zwięzłości gruntu wyznaczonej penetrometrem. Stwierdzono, że: a) liczba przejazdów mniejsza niż cztery wpływała jedynie na zagęszczenie wierzchniej warstwy gleby do poziomu 0,2 m, natomiast przy większej liczbie przejazdów wpływ ten przenosił się również na niższe warstwy profilu glebowego, b) każda z metod wykazała średnio ponad 2-krotny wzrost zagęszczenia pomiędzy profilem gleby niezagęszczonej a profilem gleby po ośmiu przejazdach kół ciągnika.

2

Wykorzystanie metody konduktometrycznej i georadarowej do identyfikacji stopnia ugniecenia wierzchniej warstwy gruntu

Akinsunmade Akinniyi, Tomecka-Suchoń Sylwia, Pysz Paweł, Karczewski Jacek, Juliszewski Tadeusz, Zagórda Mirosław, Kiełbasa Paweł

Przegląd Elektrotechniczny

|

2020

|

R. 96, nr 2

137--141

PL

W artykule przedstawiono relacje między stopniem zagęszczenia gruntu określonym penetrometrem stożkowym, przewodnością elektryczną gruntu na wybranych głębokościach jego profilu określoną konduktometrem oraz echogramem wykonanym georadarem. Badania przeprowadzono w warunkach rzeczywistych a do zagęszczania gruntu wykorzystano ciągnik rolniczy wyposażony w standardowe opony. Zidentyfikowano istotną zbieżność wyników pomiarów dla wszystkich metod pomiarowych, która pozwala stosować je wymiennie do identyfikacji nadmiernego zagęszczenia gruntu np. śladów przejazdu maszyn a także innych anomalii w zagęszczeniu gruntu pod warunkiem istnienia wyrównanych parametrów wilgotnościowych mierzonego ośrodka.

EN

The article presents the relationship between the degree of soil compaction determined by a cone penetrometer and soil electrical conductivity at selected depths of its profile determined by a conductometer and a GPR echogram. The tests were carried out in real conditions and an agricultural tractor equipped with standard tires was used for soil compaction. Significant convergence of measurement results was identified for all measurement methods, which allows them to be used interchangeably to identify excessive soil compaction, e.g. machine tracks, as well as other anomalies in soil compaction, provided that the humidity parameters of the measured medium are equal.

3

Characterization of lithological zones of the Isanlu sheet 225, North Central Nigeria, using aerogeophysical datasets

Akinsunmade Akinniyi, Nguyen Dinh Chau, Wojas Anna, Tomecka-Suchoń Sylwia

Acta Geophysica

|

2020

|

Vol. 68, no. 3

651--665

EN

Gridded aeromagnetic and aeroradiometric datasets of Isanlu sheet 225 were processed and interpreted in order to map the geological structures and characteristic lithology, as well as potential mineral ore zones in the area. Recorded aeromagnetic data were reduced to the magnetic equator before fltering operations which enhanced the magnetic anomalies. Analytic signal map was created, and subsequently a model was generated along a selected profle for better interpretation of the subsurface materials. On the aeroradiometric data were performed both enhancement and statistical operations. The lithological zones were identifed. They are metasedimentary rocks, migmatites and igneous rocks occupying varying proportions within the entire area. Some potential radioactive or precious metal ore zones were also localized. A major structure interpreted in the study area trends in the SE–NW direction. Other surface structures were also delineated and general orientation was evaluated. This information may serve as a valuable database for further prospective research and mineral exploration in the region.

4

Complex analysis of GPR signals for the delineation of subsurface subtle features

Akinsunmade Akinniyi, Tomecka-Suchoń Sylwia, Pysz Paweł

Geology, Geophysics and Environment

|

2019

|

Vol. 45, no. 4

257--267

EN

In this paper, complex signal analyses of ground penetrating radar (GPR) field data over an area of farmland in Krakow were interpreted alongside the basic filtered field data. The farmland was simulated with varying degrees of soil compaction induced by tractor movement. The focus of the study was the delineation of inherent characteristics of media through which the electromagnetic energy travelled. Fourteen GPR profiles were acquired from the area. The field data were subjected to pre- and post-processing prior to its the presentation and interpretation. Advance analysis operations on the field data which resorted in different attributes reveal more about the effects of the compaction on the soil than indicated by the basic filtered field data. Better resolution of subsurface layers boundary and lateral variation in the physical properties of the traversing media were well elucidated. The results have demonstrated that an advanced signal processing such as used in the study has ability to depict subtle characteristics of the propagating media.

5

Ground penetrating radar use in flood prevention

Tomecka-Suchoń Sylwia

Acta Geophysica

|

2019

|

Vol. 67, no. 6

1955--1965

EN

The main goal of the work is to create an automatic method of locating weak zones within flood embankments structure based on ground penetrating radar (GPR) measurements. The presented research shows the possibilities of using advanced methods of GPR signal processing and its analysis with the help of signal attributes for detecting zones threatening the stability of the structure of flood embankments. Obtained results may help in quick detection of potential weak zones of the embankments and consequently give means to ameliorate them, which may prevent damage to the embankments during rise in the level of river water. The presented analyses were carried out on GPR data obtained for the flood banks of the Rudawa River (Kraków, Poland) in the area of their visible degradation. The use of signal attributes, such as Energy, instantaneous frequency, similarity, curvature gradient, dominant frequency, allowed initial indication of anomalous zones threatening the stability of embankment. Advanced processing supported by the use of advanced filters such as GLCM, Grubbs filter threshold and Convolve Prewitt helped in the analysis of the structure of the embankments. Artificial neural networks (ANNs) in the supervised and unsupervised variants were used to perform the automatic classification of weakened zones within the embankments. The results demonstrated the usefulness of GPR geophysical method through integration of ANN in the analysis of the data.

6

Finite-difference time domain (FDTD) modeling of ground penetrating radar pulse energy for locating burial sites

Akinsunmade Akinniyi, Karczewski Jerzy, Mazurkiewicz Ewelina, Tomecka-Suchoń Sylwia

Acta Geophysica

|

2019

|

Vol. 67, no. 6

1945--1953

EN

Analysis of the finite-difference time domain (FDTD) numerical simulation of ground penetrating radar (GPR) measurement for locating burial sites is described in this paper. Effective, efficient, and reliability interpretation of GPR field data obtained from clandestine sites is very crucial in forensic investigations. The main goal of the study is the prediction of the change in the interaction of the electromagnetic incident on changes in buried bodies with time. In order to achieve this, the research involves the modeling of the GPR electromagnetic pulse energy responses to simulated changes in buried body with time with a view to understand what the results of real field measurement will give. The field measurements were conducted with GPR system manufactured by Mala Geoscience with antennae frequency of 500 MHz, 250 MHz, and 100 MHz. Responses from both synthetic and field radargrams depict the target was intercepted at same time (approximately 25 ns). The results have demonstrated that FDTD modeling is an important tool for enhancing the reliability of GPR data interpretation particularly for forensic study.

7

Correlation between agrotechnical properties of selected soil types and corresponding GPR response

Akinsunmade Akinniyi, Tomecka-Suchoń Sylwia, Pysz Paweł

Acta Geophysica

|

2019

|

Vol. 67, no. 6

1913--1919

EN

In this study, we investigated the relationship between ground-penetrating radar (GPR) response and agriculture properties of soil with a view to understanding how the constraint of soil degradation may influence the properties. GPR field data measurements were made at a location with soil types, properties, and disturbances caused by tractor movement. The data were processed, and empirical equations relating soil physical properties and material properties of soil media were considered for the analysis of the field data. The results showed a change in the reflection coefficient and increase in the GPR wave velocity when comparing the records of the initial parts of the GPR records, lasting about 2.5 ns, of the signal response of soil subjected to compaction as a result of 10 tractor passes, with those obtained prior to movement of the tractor. The summation of the absolute value of GPR wave amplitude in the analyzed results clearly shows that the amplitude of the signal corresponding to the compressed ground is twice and even three times smaller than the amplitude recorded before the tractor runs. The results prompted the design of a relatively simple method for tracking changes in soil properties based on the results of GPR measurements, which show that zones subjected to direct tire pressure are easy to delineate and are not limited to the part that is directly under the tire, but extend about 0.5 m. It thus shows that there is a relationship between the penetration resistance induced by a change in porosity and changes in the coefficient of reflectivity and the velocity of radar waves.

8

Application of GPR and seismic methods for noninvasive examination of glacial and postglacial sediments in the Psia Trawka glade: the Tatra Mts., Poland

Tomecka-Suchoń Sylwia, Gołębiowski Tomisław, Dec Jerzy, Magiera Janusz

Acta Geophysica

|

2019

|

Vol. 67, no. 6

1777--1789

EN

Presented study gives an insight into general proportions of the actual geomorphology, subglacial morphology and thickness of the drift (quaternary sediments) particularly well-pronounced glacial morphology in the Tatras and, on the other hand, the general scarcity of the data in this field. Objectives of the geophysical survey in this study were imaging of the morphology of bedrock surface under the drift (glacial and postglacial) sediments and determination of thickness of the drift and its composition. Two methods were applied: Ground Penetrating Radar (GPR) and seismic refraction profiling. GPR was used to examine drift sediments due to its high resolution and low depth of penetration. Seismic method with lower resolution but higher penetration depth gave an image of boundary between bedrock and drift. In addition, the results of seismic tomography allowed the velocity field imaging which shows changes inside the postglacial deposits. The results of the two methods used in this research suggest that points of depression exist in the subglacial morphology with a depth of about c.a. 40 below the present-day terrain surface and c.a. 25 m below surrounding subglacial surface. This trough has also been estimated to be about 150 m wide. Its considerable depth and steep slopes show that its origin can be related to erosion of subglacial water during the decay of the last (Würm) glaciation of the Sucha Woda and Panszczyca valleys.