Vpliv vira dolomitnega agregata na lastnosti samozgoščevalnega betona

• Main Author: Gošte, Neža
• Other Authors: Bokan-Bosiljkov, Violeta
• Format: Bachelor Thesis
• Language: Slovenian
• Published: N. Gošte 2019
• Subjects: Vrsta dolomitnega agregata; samozgoščevalni beton; tlačna trdnost betona; elastični modul betona; odpornost površine proti zmrzovanju in tajanju; Dolomite aggregate type; self-compacting concrete; compressive strength of concrete; modulus of elasticity of concrete; salt frost scaling resistance; info:eu-repo/classification/udc/624.014.2(497.4)(043.2); sami
• Online Access: https://repozitorij.uni-lj.si/IzpisGradiva.php?id=110959; https://repozitorij.uni-lj.si/Dokument.php?id=122688&dn=; https://plus.si.cobiss.net/opac7/bib/8927585?lang=sl

V diplomski nalogi smo se ukvarjali z ugotavljanjem reoloških in mehanskih lastnosti samozgoščevalnega betona iz dolomitnega agregata ter njegove obstojnosti. Zanimalo nas je predvsem, kako na te lastnosti vpliva vir dolomitnega agregata. Za namen preiskav smo pripravili dve sestavi samozgoščevalnega betona, ki sta vsebovali enak cement, vodocementno razmerje, dodan superplastifikator, a različen dolomitni agregat, ki smo ga dobili iz dveh različnih kamnolomov. Sami smo zamešali beton ter pripravili betonske preizkušance. Na svežih betonskih mešanicah smo preverili konsistenco z metodo razleza s posedom in določili vsebnost zraka s porozimetrom. Na strjenih betonskih preizkušancih smo ugotavljali mehanske in obstojnostne lastnosti betona. Določali smo tlačno trdnost betona ter dinamični in statični modul elastičnosti. Preiskave smo izvajali po 24-ih urah, 3-eh, 7-ih, 28-ih in 90-ih dneh. Po 28-ih dneh smo na preizkušancih določili tudi odpornost površine betona proti zmrzovanju in tajanju, pri čemer smo izvedli 20 ciklov zmrzovanja/tajanja v prisotnosti talilne soli. Rezultate preiskav smo na koncu analizirali in ocenili vpliv vira dolomitnega agregata na karakteristike betona. The graduation thesis deals with the rheological and mechanical properties of self-compacting concrete prepared using dolomite aggregate and with its durability. We were predominantly interested, how the source of dolomite aggregate affects these properties. For the purpose of research work, we prepared two self-compacting concrete mixtures that contained the same type and content of cement, the same water-to-cement ratio, the same type of superplasticizer, but different dolomite aggregate, obtained from two different quarries. The concrete mixtures were prepared and test specimens were cast in the laboratory of the Faculty of Civil and Geodetic Engineering. On fresh concrete mixtures, we tested the consistency using slump-flow test and determined the content of air bubbles in concrete using the pressure method. On hardened concrete samples, we determined mechanical properties and durability of concrete. We tested the compressive strength of concrete and the dynamic and static modulus of elasticity. We did the tests after 24 hours, 3, 7, 28 and 90 days. At the age of samples of 28 days we started to carry out salt frost scaling test. The surface of the samples was saturated with a de-icing salt and the specimens were exposed to 20 freezing/thawing cycles. Finally, we analysed the test results and evaluated the influence of the source of dolomite aggregate on the properties of self-compacting concrete.