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Abstract

The mechanical behavior of the Buda Marl lies between those of rock and soil; it is therefore appropriate to define it as both weak rock and strong soil: some marl types behave like a weak rock and others like soil. In such cases the strength parameters of the material can be determined by rock mechanical or soil mechanical laboratory investigations. Often a problem occurs when the material cannot be assigned to either of these classes, in which case neither the commonly-used rock mechanical nor the soil mechanical tools are applicable to define the strength properties of the material. In this case the mechanical parameters of the material can only be estimated in an empirical fashion. The goal of this paper is to demonstrate the rock mechanical properties of the marl, using an empirical method, which can be use to determine the physical properties of a material that is neither rock nor soil.

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Abstract

The Kiscell Clay is the most frequently-occurring rock type of Budapest, especially on the Buda side of the Danube. It occurs near the surface as well as at great depth; for the purposes of this study the upper, approximately 35 meters of the unit was investigated. The results of previous laboratory analyses were collected and more than 2000 test results evaluated. Physical properties such as plasticity index, density, void ratio, and coefficient of compressibility were tested and the results statistically analyzed. Correlation between different properties is shown in graphic form, and equations are proposed to describe the various coefficients.

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Abstract

The Oligocene clay units in the Budapest area along the new metro (subway) line show different properties than most others. They are denser and of greater strength than most of the unconsolidated ones. This paper provides an overview of their engineering geologic properties using nearly 4700 physical parameter data. These data were obtained from cores representing sampling intervals of the Kiscell Clay, on the Buda side of the Danube River. Seventeen engineering geologic parameters were used in the description of the clay. The parameter analyses show that the clay behaves as a soft rock rather than a soil.

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Stone masonry arch bridges in North Hungary represent cultural heritage values. For the maintenance and preservation of these bridges detailed mapping of lithologies and weathering forms are required. The purpose of this paper is to present the identified lithotypes, their conditions (weathering grade) and their petrophysical properties by using in situ lithological mapping, documentation of weathering forms, non-destructive tests and laboratory analyses. Furthermore these analyses demonstrate the difficulties of characterization and diagnostics of the historical construction materials. Additionally the results of condition assessments and the properties of the four different dimension stones from four different sites provide examples for the large dissimilarities regarding the strength parameters. The above-listed parameters are required as input data for stability calculations and modeling of these structures.

Open access
Pollack Periodica
Authors:
Ildikó Buocz
,
Nikoletta Rozgonyi-Boissinot
,
Ákos Török
, and
Péter Görög

This paper presents a brief summary of the main existing shear strength test methods on both intact and fractured rocks, such as the triaxial, half-half notched specimen and direct shear strength tests. A detailed description of how to carry out a direct shear strength test on rocks along discontinuities are provided, supported by test results. The analyses include the interpretation of the tests and the calculation of the maximal and residual shear strength, as well as their angle of friction and apparent cohesion. These parameters depend on the properties of the rock and the discontinuity, such as the joint surface roughness, the rock texture orientation, the filling material, the thickness of the discontinuities, the scale effect and the magnitude of the applied normal force during the test. Their effect is discussed.

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Abstract

In the Pilis Range, NW of Budapest, contemporaneous Upper Triassic platform and basin facies occur. The paper presents the extent and basic characteristics of these facies with interpretation of their depositional conditions, and summarizes the available biostratigraphic data. Based on previous and recent studies a general depositional model is displayed and the history of the basin evolution is outlined. Within the Dachstein Platform an extensional intraplatform basin (Feketehegy Basin) came into existence during the middle part of the Norian. An asymmetric basin was formed, bounded by steep and gentle slopes, respectively. The platform progradation that may have resulted in the termination of the basin began at the gentle margin probably in the latest Norian-earliest Rhaetian.

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Abstract

This paper provides test results and interpretation of the shear strength of granitic rocks. The samples were obtained from Bátaapáti (South Hungary), where the low and medium-activity nuclear waste storage facility of Hungary is under construction. The experiments were carried out under laboratory conditions by using direct shear strength tests of samples drilled and cut from larger granitic blocks. The friction angles of both the maximal and residual shear stress, as well as the cohesion, were detected for various joint systems and also for the cut surface of the granitic rock. The interpretation of test results includes the evaluation of normal stress versus shear strength for cut, moderately rough, rough and calcite-filled joints. The tests have demonstrated that the average internal angle of friction for granitic rocks exceeds 20°, with a maximum of 39° for rough surfaces. Calcite-filled joints have lower friction angles, in the range of 16–23°. The peak shear strength of granitic test specimens was between 0.8 and 4.1 MPa, depending on the surface and joint fill.

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Acta Geologica Hungarica
Authors:
János Haas
,
Ágnes Görög
,
Sándor Kovács
,
Péter Ozsvárt
,
Ilona Matyók
, and
Pál Pelikán

The basement of the Pannonian Basin is made up of tectonostratigraphic terranes of varying origin. They gradually amalgamated to form the large Alcapa and Tisza-Dacia composite terranes that were juxtaposed during the Tertiary. In North Hungary, in the basement of the Tertiary volcanic complex of the Mátra Mts and in the western part of the Bükk Mts, remnants of a Jurassic accretionary wedge were encountered. Ore exploration boreholes encountered several hundred-meter thick carbonate and siliceous shale-radiolarite successions in the basement of the Mátra Mts (Darnó Complex). Based on detailed studies of Core Recsk-109, the carbonate succession consists predominantly of grainstone with packstone-wackestone intercalations. Peloidal bioclastic grainstone is the most common texture type but sand-sized intraclasts and oncoid and ooid grains also occur locally. The most spectacular feature is the large amount of coarse to medium sand-sized fragments of calcified cyanobacteria ("Porostromata"). Platform-derived foraminifera and fragments of crinoids are also common. Gravity flows transported the carbonate detritus to the site of deposition at the lower foreslope and proximal toe-of-slope. Based on foraminifera the succession is Aalenian? or Early Bajocian in age.  In the southern part of the Bükk Mts fine-grained, graded oolitic, peloidal grainstone with shale and radiolarite interlayers occur in surface exposures and cores (Bükkzsérc Limestone Formation). These deposits were formed via turbidity currents in a basin relatively far from the carbonate producing platforms. Based on foraminifera the age of the formation is Early Bajocian-Bathonian. Radiolarian faunas suggesting Late Bajocian-Early Bathonian and Early Bathonian-Early Callovian age respectively, were found in a silicified carbonate and radiolarite succession that occurs below the Bükkzsérc Limestone with a tectonic contact. In the wider region Middle to Late Jurassic carbonate platforms and reef facies are known only in the Dinarides, in the area of the Adriatic (Dinaridic) Carbonate Platform. Coeval platform-derived redeposited carbonates and intercalated pelagic basin deposits were reported from the slopes of the Adriatic platform and the periplatform basins of the Slovenian Trough and the Bosnian Flysch Zone. These data confirm the previously suggested paleogeographic connections between the Dinaridic units and the Darnó and Bükk units during the Jurassic

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Magyar Sebészet
Authors:
Csaba Dzsinich
,
Lajos Zsíros
,
Gábor Vallus
,
Péter Berek
,
Gabriella Nyiri
,
Sándor Pellek
,
János Görög
,
László Szentpétery
, and
Tibor Pataki

Absztrakt

A mellkasi aorta sérülése a traumatológia egyik legsúlyosabb fejezetét alkotja. A nyílt és transmuralis aortasérülés helyszíni halált okoz, a mellkasi aorta tompa sérülése azonban gyors szállítással, diagnosztikával és megfelelő kezelési taktikával az esetek egy részében eredményesen kezelhető. Az aorta tompa sérülése politrauma része, a beteg sorsát az aorta sérülésének súlyossága a társsérülésekkel együtt jelentősen befolyásolja. A prioritások meghatározása alapján dönthetünk a kezelés mikéntjéről és ütemezéséről. Az azonnali, a szubakut és a konzervatív kezelés lehetőségei változatosak, alkalmazásuk kiválasztása nagy tapasztalatot és megfelelő, egyénre szabott terápiás terv követését teszi szükségessé. A kórkép változatossága egységes vezérfonal kialakítását nehezíti, ezért fontosnak tartjuk saját tapasztalataink összefoglalását és a vonatkozó irodalom áttekintését.

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Interventional Medicine and Applied Science
Authors:
Fanni Gelley
,
Gergely Zádori
,
Dénes Görög
,
László Kóbori
,
Imre Fehérvári
,
György Gámán
,
Zsuzsanna Gerlei
,
Péter Nagy
,
Enikő Sárváry
, and
Balázs Nemes

Abstract

Introduction

Recurrence of primary sclerosing cholangitis (rPSC) after liver transplantation (OLT) significantly affects longterm graft survival. We aimed to evaluate the incidence of rPSC and clinical data of these patients in Hungary.

Patients and Methods

We retrospectively analyzed data of 511 whole liver transplantations from 1995 to 2011. During the study period, 49 OLTs were performed in 43 adult patients with end-stage PSC (10%).

Results

Out of 49 OLT, 24 cases were excluded, rPSC was diagnosed in six patients (12%). Patients with rPSC had significantly higher mortality (p = 0.009) and graft loss (p = 0.009) in comparison to patients without recurrent disease. Younger recipient age, higher donor BMI was observed in the rPSC group. One patient was diagnosed with de novo IBD, the remaining five patients had worsening IBD activity in the posttransplant period. PreOLT colectomy was performed in 21% of the control and none of the rPSC group. PostOLT colectomy was performed in two rPSC patients due to severe therapy resistant colitis.

Conclusions

Recurrent PSC significantly affects long-term mortality and graft loss. Younger age at OLT, higher donor BMI and severe active IBD may be associated with PSC recurrence. PreOLT total colectomy might have protective effect against rPSC.

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