Péter Görög

Budapest University of Technology and Economics · Department of Engineering Geology and Geotechnics

Considering the creep behavior of soft and weak rocks is critical for analyzing the long-term stability of underground constructions. This paper introduces a novel creep constitutive model to characterize the creep behavior of rocks under uniaxial and triaxial stress states. The fractional derivative Abel dashpot was used to improve the Burger mode...

The creep behavior of rocks has been broadly researched because of its extensive application in geomechanics. Since the time-dependent stability of underground constructions is a critical aspect of geotechnical engineering, a comprehensive understanding of the creep behavior of rocks plays a pivotal role in ensuring the safety of such structures. V...

The Generalised Hoek-Brown (GHB) failure criterion is one of the most used criteria to study the behaviour of the rocks; affected parameters of the Hoek-Brown equation are Geological Strength Index (GSI), intact rock constant (mi), and Disturbance factor (D). GSI is one of the rock classification systems used to evaluate jointed rocks. In light of...

The significance of creep behavior in soft rocks is crucial in rock engineering, particularly when ensuring the time-dependent stability of underground structures. This study proposed a new nonlinear creep constitutive model to represent the soft rock’s creep behavior subjected to uniaxial and triaxial stress conditions. The Burger model was modifi...

Soft rocks in various forms of marly materials have an important role in the geological structure of Dalmatia (Croatia) and Budapest region (Hungary). These materials can cause serious problems in design and construction, due to their complex behavior under atmospheric conditions. For the purpose of better understanding soft rocks behavior and thei...

There are historic subsurface dimension stones in the capital of Hungary (Budapest) that were excavated in porous limestone. The stability of these subsurface openings is important, since most of them are located in urban areas, where existing buildings or new structures are planned to be built. The paper presents a detailed study considering the g...

One of the main reasons for the instability of the terrain surface is the occurrence of natural and anthropogenic cavities and the development of a crack zone around them. The existence of voids and loosening at small depths in urbanized areas can cause damage to the infrastructure. Therefore, it is important to have a good geotechnical and geophys...

The time-dependent stability of tunnels is an important and challenging topic, mainly when the tunnel is excavated in incompetent and weak rocks. The creep property of rock is one of the crucial mechanical properties of weak rock and the main factor affecting the long-term stability of rock masses. Also, water as an important environmental factor i...

Soft rocks have an important role in the geological structure of Dalmatia (Croatia) and Budapest area (Hungary). In general, soft rocks are transitional material between the hard rock and soft soil with compressive strength below 25 MPa. A lower limit of soft rock strength is a subject of many discussions in geotechnics. Most of the soft rock mater...

Construction work above previous mining area is always a great challenge from the engineering point of view. In the southern part of Budapest, the previous mining activities resulted more than a hundred thousands of square meters of cavities. These cellars cut into porous limestone with different depth, but mostly close to the surface; nowadays, th...

Nowadays, there are several existing masonry arch structures which are usually protected. Therefore, the maintenance and determination of their load-bearing capacity is a very important issue. Consequently, it is necessary to understand the behaviour of these structures, but the investigation of an old structure can cause difficulties. Nevertheless...

Four different porous limestone lithotypes were collected from the cellar system of Budapest (Hungary). All lithologies have high porosities ranging from 16 to 30%. The laboratory analyses focused on the mechanical properties testing to assess the strength changes due to water saturation. The density, ultrasonic sound wave propagation, uniaxial com...

The stability of natural and man-made cavities is a very important topic nowadays especially if it is located under new construction areas. There are a lot of residential areas in Budapest and other cities of Europe such as Rome, Paris, and Cracow with stability problems because of cavities. For stability calculations, the geometry of the cavity, s...

The cellars are usually the result of previous quarrying activities. The area of these cavities nowadays located under urban areas and usually makes difficult the urban developments. There are some areas in Budapest where cellars are found below future construction sites therefore detailed investigation of these cellar systems are required. The inv...

The paper compares the engineering geological parameters of Croatian flysch deposits and Hungarian marls with respect to slope stability. Eocene flysch deposits are widespread sediments in Central Dalmatia. They form gentle to steep slopes in the countryside and in urban areas, with risks of slope instability. Especially weathered and long-time exp...

Steep, hardly accessible cliffs of rhyolite tuff in NE Hungary are prone to rockfalls, endangering visitors of a castle. Remote sensing techniques were employed to obtain data on terrain morphology and to provide slope geometry for assessing the stability of these rock walls. A RPAS (Remotely Piloted Aircraft System) was used to collect images whic...

Low strength rhyolite tuff forms steep cliffs in NE Hungary. A multi-dimensional approach including field analysis and laboratory tests was conducted to understand the mechanical properties of the tuff and to measure discontinuity surfaces. With the help of RPAS (Remotely Piloted Aircraft System) and TLS (Terrestrial Laser Scanning), a digital terr...

Steep, and hardly accessible jointed rhyolite tuff cliff faces surround a Castle in NE-Hungary, at village of Sirok. The assessment of cliff stability required the recording of cliff geometry. Traditional surveying was not possible therefore cliff faces were 3D modelled by GNSS supported terrestrial laser scanner and UAV. The onsite engineering geo...

Siroki várhegyet alkotó riolittufa állékonysági vizsgálatát mutatja be a cikk, kiemelve a térinformatika és a mérnökgeológia együttes alkalmazását. A sziklalejtő felmérésére az erősen tagolt domborzat miatt és a nehéz megközelíthetőség miatt GNSS támogatású földi lézerszkennelés és drónos légifényképezést alkalmaztunk. Az így kapott térinformatikai...

Spectral measurements have been carried out on polished stone slabs to show the accuracy of theoretical colorimetric calculations on perceptual differences of color appearance under various standard illuminations. Effects of the different spectral characteristics of the light source on colorization of the samples have been also studied to analyze t...

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...

The Avas hill is located in the center of a town (Miskolc) in North Hungary., Several landslides occured on the slopes of the hill in the past and the sliding still continues in these days. This paper is about the steep Northern slope of the hill which densely built and its geological structure is very complex. The hill is composed of late Badenian...

Maintenance and restoration is a common problem of historical stone structures. To control the stability and to verify the load-bearing capacity of these structures there are several modeling methods from the simple approximate calculations to the difficult numerical methods. Several Hungarian stone masonry arch bridges were investigated in the pas...

A bimrock típusú csoportba olyan összetett, komplex kőzettípusokat sorolunk, melyekben a finomabb szemcséjű mátrix anyagba geotechnikailag jelentős blokkok, kavicsok találha-tók és a blokk-mátrix anyag között fellépő mechanikai feszültségek befolyásolják a kőzet szilárdságát. A bimrock típusú kőzetek nemzetközi szakirodalomba való bevezetése akkor...

This paper presents the required preparatory investigations for the construction of a masonry vault model experiment under laboratory conditions. The analyzed factors included structural design, material, loading and geometry of the model. A numerical modelling was made by Phase2 finite element program to check the performance of the masonry vault...

The first underground radioactive waste repository for low and intermediate level waste in Hungary is being built in the outskirts of the village of Bátaapáti. The total length of tunnels driven to date is over 5,200 m including two inclined access tunnels, the base tunnels and the first two emplacement chambers. The tunnels were driven in fracture...

There are more than 570 underground wine cellars that were constructed from the 13th century in the city centre of a town (Miskolc) in NE Hungary. With the recent rapid urban development and the population growth many of the cellars are endangered and there is a risk of collapse and structural damage. The present paper focuses on the stability anal...

The importance of Cultural Heritage has emerged since the early 1970s, including cultural, natural and mixed properties. Hungary is also one of those countries having great properties of importance such as historical castles, settlements, wine cellars. Northern Hungary has good advantage to develop man-made structures such as wine-cellars. The deve...

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...

The paper provides new results on the fracture surface roughness testing from the Bátaapáti National Radioactive Waste Repository project. During the calibration of modeling and design work it was necessary to develop a simple and quantitative approach to predict the Joint Roughness Coefficient (JRC) value of fracture surfaces. To reach this goal l...

In the development of new strategies for different spine fixation methods, new methods must be tested biomechanically under in vitro conditions before clinical trials can be performed. The effect of different conservation mode on the mechanical properties of vertebrae is an important question. The aim of our research was to determine the effects of...

A kutatás során a Mórágyi Gránit Formáció gránitos származó mintadarabokat elemeztünk. Az ilyen jellegű kőzetek nyírószilárdsági vizsgálatát már korábban is ismertették (Buocz et al. 2010), a jelen cikk a felületi érdesség szerepével foglalkozik. A vizsgált minták monzogránitos kőzetekből származnak és ezen belül olyanokat is elemeztünk, me-lyek tö...

ÖSSZEFOGLALÁS: A Várbazár területén épülő mélygarázs térségének mérnökgeológiai jellemzéséhez a területen mélyült fúrások által harántolt kőzetváltozatok kőzetfizikai paramétereinek megállapítása volt szükséges. A lemélyített 2 fúrás az eocén korú budai márga kőzetváltozatait tárta fel, amelyek laboratóriumi vizsgálata alapján meghatároztuk a kőzet...

A Miskolc központjában elhelyezkedő Avas domb két részre osztható a lankásabb déli és a merede-kebb északi lejtőre. A lankás déli lejtőn a 70-es években építettek tízemeletes panelházakat. Az északi lejtő jóval meredekebb, ahol kanyargós keskeny utcák mentén, jó állapotú és teljesen elhanyagolt épü-letekkel is találkozhatunk. Ezekben a közös, hogy...

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 co...

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...

A mérnökgeológiában a kőzetkörnyezet leírásának egyik — a nemzetközi gyakorlatban mindinkább használt módszere a Geológiai Szilárdsági Index (GSI), mely az elmúlt évtized alatt az egyik legjelentősebb kőzettest-értékelési mód lett. A módszer segítségével közvetve számszerűsíthető, a mérnöki tervezésben felhasználható, kőzetfizikai adatokat kapunk,...

In engineering geology the rock mass characterization can be performed by using various methods of which the Geological Strength Index (GSI) is one of the recently introduced techniques. By applying the GSI method, design parameters - such as angle of friction, modulus of elasticity, cohesion and compressive strength - can be evaluated and calculat...

Az építőmérnöki gyakorlatban egyre gyakoribb feladat a talajvízfelszín alatti rétegek szivárgási tényezőjének meghatározása. A mélyépítési munkák költségbecslésekor a munkagödör víztelenítési módját kívánja előre meghatározni a beruházó, a másik gyakori cél pedig a kitermelhető vízkészlet megállapítása a tervezett épülethűtéséhez-fűtéséhez. A geote...

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 r...

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 investigation...

A future development site of a housing estate, an abandoned-brick yard with clayey slopes was studied in details to assess slope stability and to calculate the factor of safety. The Oligocene clay, the former raw material, is divided into two different geotechnical units in the clay pit. The lower one consists of grey impermeable clays while the up...

A Gellért-hegyre tervezett sikló és a mellette kialakítandó garázs mérnökgeológiai és hidrogeológiai viszonyait mutatja be a cikk. A terület földtani viszonyainak megismerésére 10 magfúrás, kutató aknák készültek. A sikló nyomvonal budai márgában fut, a kőzet felső zónája sárga agyagos, majd ez alatt szürke cementált mészmárga rétegek találhatók. A...

The study area, a previous brick-yard, is located in the valuable lands of the Buda Mountains. The brick production ended in 1972 and the open pit was recultivated by heterogeneous landfill. The mining area was a natural slope that experienced landslides prior to the clay production. The mining activity accelerated the sliding and catastrophic land...