Balazs Vasarhelyi

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

PhD

About

148
Publications
108,563
Reads
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1,526
Citations
Additional affiliations
January 2015 - December 2020
Budapest University of Technology and Economics
Position
  • Professor (Associate)
September 2009 - February 2015
University of Pécs
Position
  • Professor (Associate)
October 2004 - October 2007
Budapest University of Technology and Economics
Position
  • PostDoc Position

Publications

Publications (148)
Conference Paper
Full-text available
After the economic boom in Iraq-Kurdistan the infrastructural reorganization began, based on the design of the highway and road network. The construction of the high number of tunnels is required because of the relief of the region thus the tracing of the roads can be better. Our Hungarian team was responsible for the verification of the Iranian-de...
Conference Paper
Full-text available
The Geological Strength Index (GSI) is widely used for numerical modelling and rock engineering design in and on rock mass. It is one of the input parameters of the Hoek-Brown failure criteria and it can also be used for estimation of the deformation modulus and the Poisson's rate of the rock mass, among the other. The determination of this value i...
Conference Paper
Full-text available
Classification of building materials, especially natural materials, is not straightforward, time-consuming and labour-intensive, as significantly more samples are required for a qualification process than for artificial materials. This investigation can be more complicate when the material behaviour (resistance) is examined against short time loadi...
Conference Paper
Full-text available
Defining the practical and proper rock failure criteria plays the most significant role in analysis and design in rock mechanics and rock engineering. Up to now, several failure criterions have been proposed for brittle rocks. Among them, Hoek-Brown failure criterion has received much attention and applied among the others for brittle rocks. The go...
Conference Paper
Full-text available
Slope stability analysis has received substantial attention in the scope of rock mechanics and rock engineering for many years. Various methods are available for analysing the stability of the vertical slope. The objective of this paper is to extend the proposed theoretical equation regarding tensile strength (t), Poisson's ratio () and bulk dens...
Article
Full-text available
The freezing technique has been employed for a long time to strengthen the mechanical properties of intact rock and rock mass; however, it has not received as much attention as it deserves. This paper thoroughly reviews the effect of freezing on the essential mechanical properties, including uniaxial compressive strength, tensile strength, and Youn...
Article
Full-text available
The mechanical properties of frozen rocks vary significantly from the properties of the same lithology under ambient temperature. The goal of this paper is to investigate these changes in the physical and mechanical properties of rocks due to saturation and freezing. Besides, the attention was paid on discovering new correlations between the mechan...
Article
Full-text available
An accurate determination of Hoek–Brown constant m i is of great significance in the estimation of the failure criteria of brittle rock materials. So far, different approaches such as rigidity index method (R-index), uniaxial compressive strength-based method, and tensile strength-based method, and the combination of these two methods (combination...
Book
Full-text available
Hazánk túlnyomó részét laza törmelékes üledékek, azaz valamilyen talajok borítják. Ezért a sziklarézsűk építése vagy a természetes sziklafalak ellenőrzése nem hétköznapi probléma, Magyarországon különleges feladatnak számít. Az állékonyság és a stabilitás számítása különösen fontos, hiszen az út- és vasútépítések melletti bevágások, nagymélységű mu...
Article
Full-text available
A comprehensive understanding of geological, structural geological, hydrogeological and geotechnical features of the host rock are essential for the design and performance evaluation of surface and underground excavations. The Hungarian National Radioactive Waste Repository (NRWR) at Bátaapáti is constructed in a fractured granitic formation, and T...
Article
Full-text available
Testing long-term properties of aggregates requires time consuming laboratory tests. Alternatively, mathematical models can also be used to describe the abrasion process of aggregates. The paper uses another approach it links long-term abrasion to rock mechanical properties to facilitate a quick assessment of long term behavior of aggregates. It ex...
Article
Full-text available
Determining linear elastic stiffness parameters is a crucial aspect of ground characterization that enables subsequent numerical analyses using finite element, discrete element, and other procedures. Before estimating global settings for a rock mass relative to a proposed excavation such as a rock slope, tunnel or cavern, it is essential to underst...
Article
Full-text available
According to its definition, Poisson's ratio is a measure of the Poisson effect, the phenomenon in which a material tends to expand in directions perpendicular to the direction of compression or, in other words, Poisson's ratio is the ratio of relative contraction to relative expansion. For the sake of simplicity, it is handled as a constant. Howev...
Article
Full-text available
Determination of the mechanical behaviour of intact rock is one of the most important parts of any engineering projects in the field of rock mechanics. The most important mechanical parameters required to understand the quality of intact rock are Young’s modulus (E), Poisson’s ratio (ν), the strength of rock (σc) and the ratio of Young’s modulus to...
Article
Full-text available
The determination of deformation parameters of rock material is an essential part of any design in rock mechanics. The goal of this paper is to show, that there is a relationship between static and dynamic modulus of elasticity (E), modulus of rigidity (G) and bulk modulus (K). For this purpose, different data on igneous, sedimentary and metamorphi...
Article
Full-text available
Although Poisson’s ratio is one of the basic rock mechanical parameters, it is less investigated than the other parameters. It can be assumed, that this material constant depends on the rigidity of the rock, among the others. The goal of this research is to find a theoretical relationship between the rigidity of the intact rock and Poisson’s ratio....
Article
Full-text available
of the long term data taking, related to one of the proposed next generation ground-based gravitational detector’s location is presented here. Results of seismic and infrasound noise, electromagnetic attenuation and cosmic muon radiation measurements are reported in the underground Matra Gravitational and Geophysical Laboratory near Gyöngyösoroszi,...
Conference Paper
Full-text available
Although freezing has been used for decades for improving the strength parameters of rock masses around underground openings, there is limited research on the behavior of frozen materials. The objective of this paper is to investigate the relationship between different mechanical properties of highly porous limestone in case of dry, water saturated...
Article
Full-text available
Understanding the quality of intact rock is one of the most important parts of any engineering projects in the field of rock mechanics. The expression of correlations between the engineering properties of intact rock has always been the scope of experimental research, driven by the need to depict the actual behaviour of rock and to calculate most a...
Conference Paper
Full-text available
The Geological Strength Index (GSI) is one of the most important input parameter for rock engineering design in case of rock masses. Recently, several quantitative determinations of this value have been developed. These methods can be used for both rock cores and tunnel faces, as well. The paper presents different methods for calculating the GSI va...
Conference Paper
Full-text available
Understanding the rock failure mechanism under dynamic loading is of high importance in rock engineering projects. It requires a model to address a coupling effect between plastic flow caused by sliding along micro-crack faces and damage evolution due to nucleation and growth of wing-cracks. The goal of this paper is to develop a self-consistent ba...
Conference Paper
Full-text available
The Geological Strength Index (GSI) is one of the most important input parameter for rock engineering design in case of rock masses. Recently, several quantitative determinations of this value have been developed. These methods can be used for both rock cores and tunnel faces, as well. The paper presents different methods for calculating the GSI va...
Conference Paper
Full-text available
Nearly 30 m high rock slope construction was necessary in soft rock condition during the construction of main road No. 21 in Hungary. Using rock mechanical laboratory test results, two different empirical rock classes (Slope Mass Rating-SMR and Q-slope) were applied to calculate the stability of the rock slope. For these calculations, the angles be...
Article
Full-text available
With the intent of making data acquisition for fractal geometry-based discrete fracture network (DFN) modeling time-efficient and automatized, a new method was established. For the automation of data retrieval from the images of the studied surfaces, a series of image-processing operations and MATLAB algorithms have been developed. The method allow...
Chapter
Full-text available
The mechanical properties of frozen rocks are very different from the properties of the same lithologies under ambient temperature. The goal of this paper is to describe the changes in the physical parameters of rocks caused by freezing. In addition, estimations are given on how these parameters are influenced by the intrinsic properties of rocks....
Preprint
of the long term data taking, related to one of the proposed next generation ground-based gravitational detector's location is presented here. Results of seismic and infrasound noise, electromagnetic attenuation and cosmic muon radiation measurements are reported in the underground Matra Gravitational and Geophysical Laboratory near Gy\"ongy\"osoro...
Article
Full-text available
The goal of this paper is to present the influence of the water saturation of the intact rock on different mechanical parameters , such as internal friction angle, cohesion, Hoek-Brown constant (m i). Analyzing the previously published results, it was found that due to water saturation both the uniaxial com-pressive strength and tensile strength de...
Article
Full-text available
The Hoek-Brown (H-B) empirical failure envelope is widely used for calculating the mechanical behavior of the rock mass. An important input parameter of the H-B failure envelope is the Geological Strength Index (GSI), which was developed for the description of rock structure and block surface conditions. Using the GSI, the mechanical behavior of th...
Conference Paper
Full-text available
Hydraulic fracturing results vary based on the physical and mechanical characteristics of intended area and state of stresses. This paper examines effects of homogeneity and non-homogeneity of rock samples and state of stresses on the outcomes of hydraulic fracturing in laboratory scale. Hence, 3 different types of cylindrical rock samples with dif...
Article
Full-text available
Matra Gravitational and Geophysical Laboratory (MGGL) has been established near Gy\"ongy\"osoroszi, Hungary in 2015, in the cavern system of an unused ore mine. The Laboratory is located at 88~m below the surface, with the aim to measure and analyse the advantages of the underground installation of third generation gravitational wave detectors. Spe...
Article
Full-text available
The knowledge of the main mechanical constants of a rock mass (such as strength, deformability and the Poisson’s ratio) is one of the most important for rock engineering design on or in rock mass. Until now, several empirical relationships were determined for calculating these material constants based on both the quality of the studied rock mass (i...
Conference Paper
Full-text available
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...
Conference Paper
Full-text available
Elevated temperature causes changes in mechanical properties of rock, due to thermal effect and mineralogical transformations, which show great varieties for different lithologies. The present paper provides information on seven different sandstones. The studied predominantly quartz sandstones show different petrology from fine-grained to coarse-gr...
Conference Paper
Full-text available
During the design process in rock engineering Hoek-Brown failure envelope is used for the determination of rock mass failure envelope mainly in brittle rocks. An important input parameter of the Hoek-Brown failure envelope is the Geological Strength Index (GSI), which varies between 0 and 100, and concentrates on the description of rock structure a...
Conference Paper
Full-text available
A sókőzetek mechanikai tulajdonságainak vizsgálta gyakorlati szempontból is nagy jelentőségű, hiszen só dómokban van a világ szénhidrogén készletének egy jelentős része valamint a radioaktív hulladékok egyik potenciális befogadó kőzeteként is ismertek a sók. Először bemutatjuk a Parajdi sóbánya földtani és vízföldtani környezetét, Erdély geológiai...
Conference Paper
Full-text available
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...
Conference Paper
Full-text available
A cikk a lemezeknél használt ágyazási tényező közelítő számítási módszereit részletesen elemzi és összehasonlítja, hogy a bemenő talajparaméterek milyen hatással vannak az ágyazási tényező számértékére. A kapott eredményeket végeselemes programban tovább elemeztem, ipari padlók esetén, majd elvégeztem a közelítő képletek érzékenységvizsgálatát. Vég...
Article
Full-text available
The Hoek–Brown empirical failure envelope is widely used for determining the strength of brittle intact rock and rock masses. One of the two independent parameters in the formula is the Hoek–Brown’s material constant (mi), which has several uncertainties, since it relies on a set of triaxial tests. The present paper introduces a new approach to det...
Article
Full-text available
A Mátrai Gravitációs és Geofi zikai Laboratórium (MGGL) a rekultiváció alatt álló gyöngyösoroszi mélyművelésű bányában épült 2015-ben. A 88 m-rel a földfelszín alatt található létesítményben a harmadik generációs gravitációshullám-detektorok föld alatti telepítésének és folyamatos működésének lehetőségét vizsgáljuk. Szeizmikus, infrahang- és elektr...
Conference Paper
Full-text available
Consistent application of “Design as you go”-principle is especially important during the design and construction of National Radioactive Waste Repository (Hungary). Due to the geological and hydrogeological constraint discovered within the previously licensed disposal zone during the construction, the area available for safe final disposal became...
Conference Paper
Full-text available
A kőzettestben/kőzettesten való tervezésnél, a kőzettest törési határgörbéjének meghatározása az ún. Hoek-Brown törési határgörbével történik. Ennek egyik bemenő paramétere a kőzettestet leíró, annak tagoltsági, szerkezeti állapotát figyelembe vevő Geológiai Szilárdsági Index (GSI), melynek értéke 0 és 100 között változhat. A cikk célja a Bátaapáti...
Conference Paper
Full-text available
Rideg kőzetek törési határgörbéjének pontos megadására ma már egyre inkább elterjedt a Hoek-Brown törési határfeltétel meghatározása, mind ép kőzet, mind kőzettest esetén. Az összefüggés felhasználásánál az egyik nehézséget az ún. Hoek-Brown paraméter felvétele jelenti: pontos kiméréséhez igen nagyszámú minta triaxiális vizsgálat szükséges, míg egy...
Conference Paper
Full-text available
Épületek helyreállításánál, az építési kőanyag felhasználhatóságánál egyik probléma a tűzeset következtében bekövetkező változások megismerése, modellezése. Korábbi kutatások próbálták kimutatni, hogy egy adott kőzet esetén hőciklus hogyan változtatja meg a kőzet szilárdságát. Az ilyen jellegű mérési eredmények nem mutattak egyértelmű tendenciákat,...
Conference Paper
Full-text available
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...
Conference Paper
Full-text available
A primer feszültségállapot főkomponens értékei alapvető fontosságúak a felszín alatti terek tervezéséhez. A nehézségi erő egy függőleges feszültséget eredményez (σv), amely a mély-ség felé haladva lineárisan növekszik. A kőzettestben fellépő vízszintes feszültség elméleti úton történő meghatározása már jóval nehezebb, így a horizontális síkban fell...
Article
Full-text available
The integrated evaluation of borecores from the Mezősas-Furta fractured metamorphic hydrocarbon reservoir suggests significantly distinct microstructural and rock mechanical features within the analysed fault rock samples. The statistical evaluation of the clast geometries revealed the dominantly cataclastic nature of the samples. Damage zone of th...
Conference Paper
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The investigated copper mine is located in the north of Hungary at the Mátra mountain range. There are several mines in this volcanic mountain, which have been quarried since the early medieval ages. This abandoned heavy and non-ferrous metal mine is about 340-m deep. Mine closure had become necessary due to environmental reasons, because the store...
Conference Paper
Full-text available
A fractured rock mass is divided by the fracture sets into mixed shapes of blocks and wedges. The geotechnical parameters of the rock mass are obviously dominated by the presence and the spatial distribution of fracture sets. In rock engineering, the determination of geotechnical parameters of rock masses is a key issue for the prediction of expect...
Conference Paper
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The safe management of radioactive wastes and spent fuels is one of the greatest technicalscientific challenges of 21st century. Radioactive wastes and spent fuels must be isolated safely from the biosphere until they become harmless as a result of decay process of radioisotopes. It takes even a few hundred thousands or one million years in some ca...
Conference Paper
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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...
Conference Paper
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Volcanic tuffs were tested under laboratory conditions to obtain data on the influence of water content on the strength. The studied lithologies included rhyolite tuff from NE Hungary, andesite tuff from Central Hungary and basalt tuff from central western Hungary. Tests included the determination of density, ultrasonic pulse wave velocity, the uni...
Conference Paper
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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...
Article
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The geologic, geotechnical and rock mechanical background of the area, which includes an underground cavern system, is very complex. Initially, to describe the rock mass properties, the RMR and Q systems were used, while the rock support system was based solely on the Q system. Later, during construction of the repository chambers, the GSI system w...
Article
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The purpose of this paper is to analyze the sensitivity of the various constants of the different mechanical equations that depend on the Geological Strength Index (GS I) and the disturbance factor (D). Recently, both the Hoek-Brown failure criteria and the Hoek-Diederichs equations for determining the rock mass moduli are widely used in rock mecha...
Conference Paper
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Jelen cikk a Bátaapáti Nemzeti Radioaktívhulladék-tárolót befogadó kőzettest monzogránit és monzonit laboratóriumi kőzetmintáin kétirányú nyúlásmérő bélyeges deformációméréssel elvégzett egytengelyű nyomószilárdság mérések új szempontú mérési módszerét és értelmezését mutatja be. A mérések során a rideg tönkremenetel jellegzetes károsodási szakasza...