Behavior of Bentonite Under Nuclear Waste Repository Conditions: Insights from a Thermo-hydro-mechanical Model Based on Hypoplasticity

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F24%3A10488841" target="_blank" >RIV/00216208:11310/24:10488841 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1007/978-981-99-9057-3_18" target="_blank" >https://doi.org/10.1007/978-981-99-9057-3_18</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1007/978-981-99-9057-3_18" target="_blank" >10.1007/978-981-99-9057-3_18</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Behavior of Bentonite Under Nuclear Waste Repository Conditions: Insights from a Thermo-hydro-mechanical Model Based on Hypoplasticity

Popis výsledku v původním jazyce

Advanced modeling is fundamental for reproducing non-linear and coupled behaviors in expansive soils, especially in unsaturated and non-isothermal conditions. In this contribution, we provide an overview of the recent developments of a modeling approach based on the theory of hypoplasticity, specialized for expansive clays under a double-structure framework and enhanced with thermo-hydraulic and thermo-mechanical couplings at both structural levels. The model, plugged into a single-element driver - in turn introduced in an in-house finite-element solver - has been calibrated on element-volume experiments on MX-80 and B75 bentonites, which are candidate materials for buffer layers in deep geological repositories of radioactive waste. The so-calibrated parameters were then utilized in simulations of laboratory-scale tests, aiming at reproducing the response and homogenization of buffer layers (compacted bentonite blocks and/or pellets) under realistic combinations of hydration and prolonged heating. The relative simplicity of the hypoplastic formulation - featuring key parameters with clear physical meaning - has proven successful in model simulations, which exhibited a reasonable matching between predicted and experimental trends of saturation, volume change, and swelling pressure development under varying temperature. Within the framework of ongoing collaborative projects, further model improvements are envisaged, with the aim to offer better formulations of microstructural behaviors and improved computational efficiency.

Název v anglickém jazyce

Behavior of Bentonite Under Nuclear Waste Repository Conditions: Insights from a Thermo-hydro-mechanical Model Based on Hypoplasticity

Popis výsledku anglicky

Advanced modeling is fundamental for reproducing non-linear and coupled behaviors in expansive soils, especially in unsaturated and non-isothermal conditions. In this contribution, we provide an overview of the recent developments of a modeling approach based on the theory of hypoplasticity, specialized for expansive clays under a double-structure framework and enhanced with thermo-hydraulic and thermo-mechanical couplings at both structural levels. The model, plugged into a single-element driver - in turn introduced in an in-house finite-element solver - has been calibrated on element-volume experiments on MX-80 and B75 bentonites, which are candidate materials for buffer layers in deep geological repositories of radioactive waste. The so-calibrated parameters were then utilized in simulations of laboratory-scale tests, aiming at reproducing the response and homogenization of buffer layers (compacted bentonite blocks and/or pellets) under realistic combinations of hydration and prolonged heating. The relative simplicity of the hypoplastic formulation - featuring key parameters with clear physical meaning - has proven successful in model simulations, which exhibited a reasonable matching between predicted and experimental trends of saturation, volume change, and swelling pressure development under varying temperature. Within the framework of ongoing collaborative projects, further model improvements are envisaged, with the aim to offer better formulations of microstructural behaviors and improved computational efficiency.

Druh

D - Stať ve sborníku

CEP obor

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OECD FORD obor

10505 - Geology

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2024

Kód důvěrnosti údajů

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

Název statě ve sborníku

Engineering Geology for a Habitable Earth: IAEG XIV Congress 2023 Proceedings Vol. 1, Chengdu, China

ISBN

978-981-9990-56-6

ISSN

1863-5520

e-ISSN

1863-5539

Počet stran výsledku

16

Strana od-do

231-246

Název nakladatele

Springer Nature

Místo vydání

Cham

Místo konání akce

Chengdu, China

Datum konání akce

21. 9. 2023

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

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