Shrinkage of various types of portland clinker-based cements with respect to their hydration degree

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21110%2F20%3A00341203" target="_blank" >RIV/68407700:21110/20:00341203 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.14311/AP.2020.60.0088" target="_blank" >https://doi.org/10.14311/AP.2020.60.0088</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.14311/AP.2020.60.0088" target="_blank" >10.14311/AP.2020.60.0088</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Shrinkage of various types of portland clinker-based cements with respect to their hydration degree

Popis výsledku v původním jazyce

The volume changes of cement based composites are significantly exhibited in the hardening process. Initial phases of the hardening are complemented by the expansion due to the heat evolution that is subsequently alternated by the shrinkage. Both could cause a crack initiation. It is evident that ultimate volume changes of cement based composites are a complex process, because the final shrinkage is determined by the binder used, exposition and also by the previous history. The paper focuses on the evaluation of the main types of cements based on the Portland clinker by using a conventional procedure for the determination of the shrinkage on the standard cements mortars. These mortars were exposed to drying after 1 and 3 days of curing, related to the actual degree of hydration, which was estimated on the basis of compressive strength development. The hydration process was additionally monitored using thermogravimetry on the accompanying paste specimens during one year. The performed experimental program confirmed the essential sense of the curing regime especially for blended cement systems, which exhibited very low values of the hydration degree at applied curing intervals. Despite the slightly higher values of shrinkage of blended cements, the obtained results signalize the crucial effect of prolonged curing for these types of binders. The conclusion highlighted the necessity of taking into consideration the hydration degree during cement testing by using the conventional contact method. Otherwise, the simple interpretation leads to an overestimation of the less-suitable material solution.

Název v anglickém jazyce

Shrinkage of various types of portland clinker-based cements with respect to their hydration degree

Popis výsledku anglicky

The volume changes of cement based composites are significantly exhibited in the hardening process. Initial phases of the hardening are complemented by the expansion due to the heat evolution that is subsequently alternated by the shrinkage. Both could cause a crack initiation. It is evident that ultimate volume changes of cement based composites are a complex process, because the final shrinkage is determined by the binder used, exposition and also by the previous history. The paper focuses on the evaluation of the main types of cements based on the Portland clinker by using a conventional procedure for the determination of the shrinkage on the standard cements mortars. These mortars were exposed to drying after 1 and 3 days of curing, related to the actual degree of hydration, which was estimated on the basis of compressive strength development. The hydration process was additionally monitored using thermogravimetry on the accompanying paste specimens during one year. The performed experimental program confirmed the essential sense of the curing regime especially for blended cement systems, which exhibited very low values of the hydration degree at applied curing intervals. Despite the slightly higher values of shrinkage of blended cements, the obtained results signalize the crucial effect of prolonged curing for these types of binders. The conclusion highlighted the necessity of taking into consideration the hydration degree during cement testing by using the conventional contact method. Otherwise, the simple interpretation leads to an overestimation of the less-suitable material solution.

Druh

J_SC - Článek v periodiku v databázi SCOPUS

CEP obor

—

OECD FORD obor

20505 - Composites (including laminates, reinforced plastics, cermets, combined natural and synthetic fibre fabrics; filled composites)

Projekt

<a href="/cs/project/GA19-11027S" target="_blank" >GA19-11027S: Betonárenský kal - nebezpečný odpad nebo druhotná surovina?</a><br>

Návaznosti

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

Rok uplatnění

2020

Kód důvěrnosti údajů

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

Název periodika

Acta Polytechnica

ISSN

1210-2709

e-ISSN

1805-2363

Svazek periodika

60

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

CZ - Česká republika

Počet stran výsledku

10

Strana od-do

88-97

Kód UT WoS článku

000531015400001

EID výsledku v databázi Scopus

2-s2.0-85084573077