Fracture properties of cement hydrates determined from mircobending tests and multiscale modeling

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21110%2F18%3A00322893" target="_blank" >RIV/68407700:21110/18:00322893 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Fracture properties of cement hydrates determined from mircobending tests and multiscale modeling

Popis výsledku v původním jazyce

The paper shows experimental results received from bending tests performed on micro-beams fabricated with focused ion beam milling. The micro-beams were bent by nanoindenter and load-displacement curves recorded. From that, tensile strength and fracture energy were deducted for individual cement paste constituents at the level of a few micrometers. The tensile strength of the C-S-H rich inner product reached 700 MPa while the supremum of fracture energy was in the range of 4-20 J/m2. The experimentally obtained values served for verification of the multi-scale numerical model that was built for scales starting from C-S-H globules (1-100 nm) to cement paste level (up to 1-100 µm). Simulation of random packing of C-S-H globules reproduced well experimental data, yielding cohesive stress of the globule as 2500 MPa. A weak size effect was found on the scale of C-S-H up to 1000 nm, signalizing high ductility and weak strain localization. Further extension to cement paste was proposed, introducing defects responsible for further strength reduction on scaling.

Název v anglickém jazyce

Fracture properties of cement hydrates determined from mircobending tests and multiscale modeling

Popis výsledku anglicky

The paper shows experimental results received from bending tests performed on micro-beams fabricated with focused ion beam milling. The micro-beams were bent by nanoindenter and load-displacement curves recorded. From that, tensile strength and fracture energy were deducted for individual cement paste constituents at the level of a few micrometers. The tensile strength of the C-S-H rich inner product reached 700 MPa while the supremum of fracture energy was in the range of 4-20 J/m2. The experimentally obtained values served for verification of the multi-scale numerical model that was built for scales starting from C-S-H globules (1-100 nm) to cement paste level (up to 1-100 µm). Simulation of random packing of C-S-H globules reproduced well experimental data, yielding cohesive stress of the globule as 2500 MPa. A weak size effect was found on the scale of C-S-H up to 1000 nm, signalizing high ductility and weak strain localization. Further extension to cement paste was proposed, introducing defects responsible for further strength reduction on scaling.

Druh

D - Stať ve sborníku

CEP obor

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OECD FORD obor

20101 - Civil engineering

Projekt

<a href="/cs/project/GA17-05360S" target="_blank" >GA17-05360S: Lomové vlastnosti amorfních a krystalických materiálů stanovené pomocí nanoindentace a fokusovaného iontového svazku v malém měřítku</a><br>

Návaznosti

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

Rok uplatnění

2018

Kód důvěrnosti údajů

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

Název statě ve sborníku

Computational Modelling of Concrete Structures

ISBN

978-1-138-74117-1

ISSN

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e-ISSN

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Počet stran výsledku

7

Strana od-do

113-119

Název nakladatele

CRC Press

Místo vydání

Boca Raton

Místo konání akce

Bad Hofgastein

Datum konání akce

26. 2. 2018

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

000461335800013