Determination of static moduli in fractured rocks by T-matrix model

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985831%3A_____%2F17%3A00479393" target="_blank" >RIV/67985831:_____/17:00479393 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00025798:_____/17:00000151 RIV/00216208:11310/17:10363703

Výsledek na webu

<a href="http://actamont.tuke.sk/pdf/2017/n1/3chalupa.pdf" target="_blank" >http://actamont.tuke.sk/pdf/2017/n1/3chalupa.pdf</a>

DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Determination of static moduli in fractured rocks by T-matrix model

Popis výsledku v původním jazyce

This article compares static moduli determined using uniaxial tests and dynamic moduli calculated from elastic wave propagation velocities. On the example of limestones, we present the fact that for isotropic and intact rock, static and dynamic moduli correspond to each other over a broad range of frequencies. In damaged rock (cracks, weathering), a difference occurs and static moduli decrease. To include the effect of damage, T-matrix model has been selected. Dynamic moduli, porosity, density changes and information about properties of macroscopic cracks are necessary data for model calculation. These data are provided by other well logging methods such as an acoustic log with full waveform registration, density log, neutron log and acoustic scanner. Using all these data, a T-matrix model can predict static moduli from dynamic moduli. As we are dealing with well log data, we calculated vertical component of the elastic tensor only. This component is represented by Young's modulus E and Poisson's ratio.. The functionality of the model has been verified on real well logging data and corresponding limestone specimens acquired from borehole core. The differences between values of E modulus, originally up to 20 %, decreased to values similar to differences in intact rock, i.e. the order of the first units of percent. In the case of. values, demonstrable reduction of dynamic values, approaching static values was achieved, the resulting difference being less than 15 %.

Název v anglickém jazyce

Determination of static moduli in fractured rocks by T-matrix model

Popis výsledku anglicky

This article compares static moduli determined using uniaxial tests and dynamic moduli calculated from elastic wave propagation velocities. On the example of limestones, we present the fact that for isotropic and intact rock, static and dynamic moduli correspond to each other over a broad range of frequencies. In damaged rock (cracks, weathering), a difference occurs and static moduli decrease. To include the effect of damage, T-matrix model has been selected. Dynamic moduli, porosity, density changes and information about properties of macroscopic cracks are necessary data for model calculation. These data are provided by other well logging methods such as an acoustic log with full waveform registration, density log, neutron log and acoustic scanner. Using all these data, a T-matrix model can predict static moduli from dynamic moduli. As we are dealing with well log data, we calculated vertical component of the elastic tensor only. This component is represented by Young's modulus E and Poisson's ratio.. The functionality of the model has been verified on real well logging data and corresponding limestone specimens acquired from borehole core. The differences between values of E modulus, originally up to 20 %, decreased to values similar to differences in intact rock, i.e. the order of the first units of percent. In the case of. values, demonstrable reduction of dynamic values, approaching static values was achieved, the resulting difference being less than 15 %.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

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OECD FORD obor

10505 - Geology

Projekt

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Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Acta Montanistica Slovaca

ISSN

1335-1788

e-ISSN

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Svazek periodika

22

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

SK - Slovenská republika

Počet stran výsledku

10

Strana od-do

22-31

Kód UT WoS článku

000410998400003

EID výsledku v databázi Scopus

2-s2.0-85018837564