Chemical resistance of cement paste to the action of deionized water

doctoral thesis

• Title (croatian): Kemijska otpornost cementne paste prema djelovanju deionizirane vode
• Author: Marija Đuroković
• Mentor: Dubravka Matković-Čalogović (mentor)
• Mentor: Ivan janotka https://orcid.org/0000-0002-3601-5277 (komentor)
• Committee member: Sanda Rončević (predsjednik povjerenstva)
• Committee member: Dubravka Matković-Čalogović (član povjerenstva)
• Committee member: Jelena Bleiziffer (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Chemistry); Zagreb
• Defense date and country: 2019-12-19, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry
• Universal decimal classification (UDC): 54 - Chemistry. Crystallography. Mineralogy

Abstract

Introduction of new, sustainable materials into the existing civil engineering standards
requires durability data for different degradation processes. Unfortunately, durability tests are
not standardized. In this work degradation process of decalcification, also called leaching, of
cement pastes was studied. The research was conducted on three different immature cement
pastes. Two Portland cements based on calcium silicate or aluminate compounds and a
cement based on calcium sulfoaluminate compounds were used for preparation of cement
pastes. The change in chemical composition of cement pastes and pore solutions, phase
compositions, microstructures of cement pastes and their mechanical properties (strength,
modulus of elasticity, dimensional and mass stability) were observed during a 365 days
leaching period. The results indicate no significant impact of leaching on microstructure,
modulus of elasticity, dimensional and mass stability. The observed strength decrease
correlates with the observed changes in phase and chemical composition of the cement pastes
and pore solutions.

Abstract (croatian)

Uvođenje novih materijala u postojeće građevinske norme zahtijeva podatke o trajnosnim
svojstvima novih materijala. Nažalost, ispitivanja trajnosnih svojstava materijala nisu
standardizirana. U ovom radu je opisano istraživanje procesa degradacije dekalcifikacijom ili
izluživanjem. Istraživanje je provedeno na tri različite nezrele cementne paste. Dva tipa
portlandskog cementa izgrađenih od kalcijevih silikata ili aluminata i cement izgrađenog od
kalcijevih sulfoaluminata korišteni su za izradu uzoraka cementnih pasti u ovom istraživanju.
Praćene su promjene kemijskog sastava cementnih pasta i pornih otopina, faznog sastava,
mikrostrukture cementne paste kao i mehaničkih svojstava (čvrstoće, modula elastičnosti,
promjene dimenzija i mase) u periodu izluživanja od 365 dana. Rezultati ispitivanja ne
pokazuju značajan utjecaj izluživanja na mikrostrukturu, modul elastičnosti, dimenzionalnu i
masenu stabilnosti. Uočeni pad čvrstoće povezan je s učenim promjenama faznog i kemijskog
sastava cementnih pasti i pornih otopina.

• Keywords: Calcium sulfoaluminate cement; cement paste; leaching; Portland cement
• Keywords (croatian): cementna pasta; kalcijev sulfoaluminatni cement; izluživanje; portlandski cement
• Language: english
• URN:NBN: urn:nbn:hr:217:449477
• Study programme: Title: Doctoral study in chemistry; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje prirodnih znanosti, polje kemija (doktor/doktorica znanosti, područje prirodnih znanosti, polje kemija)
• Type of resource: Text
• Extent: 160 str. ; 30 cm
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-01-27 13:18:22