Vpliv dodatkov na razporeditev vode in trdnostne karakteristike 3D tiskanih preizkušancev z uporabo metode selektivne aktivacije vezanja cementa

magistrsko delo

Maja Marić (Author), Violeta Bokan-Bosiljkov (Mentor), Janko Logar (Thesis defence commission member), Dirk Lowke (Co-mentor)

Abstract

Dodatki, kot sestavine mešanic v navadni tehnologiji betona, so predmet intenzivnih raziskav v gradbeništvu. Izkušnje in izzive v tehnologiji 3D tiskanja lahko nadgradimo z znanjem in izkušnjami navadne tehnologije betona, zato kemični dodatki betonu lahko pospešijo razvoj 3D tiskanja z betonom. Raziskave v okviru magistrske naloge so bile usmerjene v preizkušanje vpliva različnih kemičnih dodatkov na porazdelitev vode v cementno-agregatni mešanici in s tem možnosti izboljšanja trdnostnih karakteristik ter natančnosti izmer 3D tiskanih betonskih preizkušancev. Z uporabo metode selektivne aktivacije vezanja cementa in dodatkov v aktivacijski tekočini smo natisnili različne serije preizkušancev, ki so se razlikovale v kombinaciji izbranih parametrov. Študirali smo vpliv različnih vodocementnih razmerij, vrst cementa in cementno-agregatnih razmerij. Za vsako serijo preizkušancev smo natisnili tudi referenčne preizkušance, kjer je aktivacijska tekočina vsebovala samo vodo. Tlačno in upogibno natezno trdnost preizkušancev smo določili po 1 in po 7 dneh (DIN EN 196-1). Porazdelitev vode v preizkušancu smo izmerili takoj po končanem tiskanju. Pravilnost oblike betonskih preizkušancev smo ocenili na podlagi razlike v dimenziji prereza med željeno in doseženo obliko. Rezultati so pokazali, da ima dodatek PVA najboljše lastnosti izmed preiskanih dodatkov. PVA omogoči večanje tlačne trdnosti natisnjenih preizkušancev z večanjem vodo-cementnega razmerja in večanjem deleža cementa v mešanici. Istočasno se izboljšajo tudi geometrijske karakteristike preizkušanca.

Keywords

civil engineering;master thesis;3D printing;selective binding cement activation method;hardened properties;chemical additives;water distribution;

Data

Language:	English
Year of publishing:	2017
Typology:	2.09 - Master's Thesis
Organization:	UL FGG - Faculty of Civil and Geodetic Engineering
Publisher:	[M. Marić]
UDC:	691.322(043.3)
COBISS:	8069473
Views:	952
Downloads:	432
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	Slovenian
Secondary title:	Effect of additives on water distribution and hardened properties of 3D printed specimens using selective binding cement activation method
Secondary abstract:	The additives in common concrete technology have already been researched in various aspects. In the act of 3D printing development the large experiences of common technology may be applied and upgraded to satisfy demands and challenges of promising technology. The objective of this study was to examine the effects of chemical additives on water distribution with the main aim to improve the hardened properties and to improve the shape accuracy of 3D printed specimens using selective cement binding activation method. To reach the improval the effect of different additives in combination with different cement types, water to cement ratios and cement to aggregate ratios was investigated. With the selective cement activation method, produced specimens were printed for each combination of studied parameters, in order to determine which mixture produce specimens with the highest strength and shape accuracy. For each combination of parameters also specimens with only water as an activation fluid were printed as a reference. The water distribution was quantified after printing. Compressive and bending tensile strengths were tested according to DIN EN 196-1. Shape accuracy was defined by measuring the dimensions of specimens cross-section area. Those properties were examined for each combination of parameters after 1 day and 7 days. Results showed that PVA possess the best properties among the studied additives. When PVA additive was used, strength of printed specimens was increasing with increasing of water to cement ratio. Moreover, the shape accuracy was also improved.
Secondary keywords:	gradbeništvo;stavbarstvo;magistrska dela;3D tiskanje;metoda selektivne aktivacije vezanja cementa;mehanske lastnosti;kemični dodatki v betonu;razporeditev vode;
Type (COBISS):	Master's thesis/paper
Study programme:	0
Embargo end date (OpenAIRE):	1970-01-01
Thesis comment:	Univ. v Ljubljani, Fak. za gradbeništvo in geodezijo
Pages:	XX, 76 str., [6] str. pril.
ID:	9605253