Fluid-Like Behavior of Crushed Rock Flows

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F22%3A10448876" target="_blank" >RIV/00216208:11310/22:10448876 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=6pQ-XE.70e" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=6pQ-XE.70e</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1029/2021JF006523" target="_blank" >10.1029/2021JF006523</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Fluid-Like Behavior of Crushed Rock Flows

Popis výsledku v původním jazyce

The puzzle of the unexpectedly high mobility of large geophysical flows has been reported as &quot;solved&quot; many times since Albert Heim drew attention to it after a disastrous landslide at Elm, Switzerland. However, the mechanism of high mobility remains mysterious. A series of high-speed rotary shear experiments on particles of different minerals was conducted to explore the high mobility flow-like behavior of crushable dense granular flow. We found that the flow behavior was more explicable when the shear resistance was considered as a viscous resistance rather than as a frictional resistance. We also found that for the crushable material, the viscosity dramatically decreased and reached a constant and relatively low value, which controlled the high fluidity and hypermobility of large geophysical flows such as rock avalanches. More precisely, there are two phases of the flow behavior, that are separated at a weakening point in the accumulating strain for crushable material. The first phase was a simple Newtonian or non-Newtonian-like flow. The second phase was more complex, in which the flow viscosity decreased profoundly and reached a constant viscous resistance at a considerable strain. This finding is important for explaining the hypermobility of many large geophysical processes, such as rock avalanche motion, natural faulting and crater collapse. In particular, we demonstrate that the behavior of rock avalanches is similar to that of complicated fluids with extensive weakening and that the viscosity of this special &quot;liquid&quot; is as low as 500 Pa.s. This finding can also help improve the accuracy and reliability of the numerical simulation of rock avalanches by using the viscous model obtained from the experiments.

Název v anglickém jazyce

Fluid-Like Behavior of Crushed Rock Flows

Popis výsledku anglicky

The puzzle of the unexpectedly high mobility of large geophysical flows has been reported as &quot;solved&quot; many times since Albert Heim drew attention to it after a disastrous landslide at Elm, Switzerland. However, the mechanism of high mobility remains mysterious. A series of high-speed rotary shear experiments on particles of different minerals was conducted to explore the high mobility flow-like behavior of crushable dense granular flow. We found that the flow behavior was more explicable when the shear resistance was considered as a viscous resistance rather than as a frictional resistance. We also found that for the crushable material, the viscosity dramatically decreased and reached a constant and relatively low value, which controlled the high fluidity and hypermobility of large geophysical flows such as rock avalanches. More precisely, there are two phases of the flow behavior, that are separated at a weakening point in the accumulating strain for crushable material. The first phase was a simple Newtonian or non-Newtonian-like flow. The second phase was more complex, in which the flow viscosity decreased profoundly and reached a constant viscous resistance at a considerable strain. This finding is important for explaining the hypermobility of many large geophysical processes, such as rock avalanche motion, natural faulting and crater collapse. In particular, we demonstrate that the behavior of rock avalanches is similar to that of complicated fluids with extensive weakening and that the viscosity of this special &quot;liquid&quot; is as low as 500 Pa.s. This finding can also help improve the accuracy and reliability of the numerical simulation of rock avalanches by using the viscous model obtained from the experiments.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10505 - Geology

Projekt

<a href="/cs/project/GJ20-28853Y" target="_blank" >GJ20-28853Y: Vliv termohydromechanického sdružení na svahové deformace v expanzních jílech: pokročilé experimenty a hypoplastické modelování</a><br>

Návaznosti

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

Rok uplatnění

2022

Kód důvěrnosti údajů

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

Název periodika

JGR: Earth Surface

ISSN

2169-9003

e-ISSN

2169-9011

Svazek periodika

127

Číslo periodika v rámci svazku

10

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

16

Strana od-do

e2021JF006523

Kód UT WoS článku

000865790900001

EID výsledku v databázi Scopus

2-s2.0-85141664200