Priprava injekcijskih mešanic na osnovi dolomitnega polnila za kamnite zidove : magistrsko delo

Rojc, Kristjan (author), Bosiljkov, Vlatko (mentor), Štukovnik, Petra (comentor)

V magistrski nalogi je predstavljena priprava injekcijskih mešanic na osnovi dolomitnega polnila z različnimi mineralnimi vezivi za injektiranje kulturnozgodovinskih objektov. Pripravili in testirali smo injekcijske mešanice, ki so kompatibilne s sestavinami kamnitih zidov kulturne dediščine. Magistrska naloga je eksperimentalne narave in je v celoti zasnovana v obliki različnih preiskav svežih in strjenih injekcijskih mešanic na cilindričnih preizkušancih in standardnih prizmah. Injekcijske mešanice smo pripravili na osnovi hidratiziranega apna, apna z dodatkom tufa ter apna z dodatkom cementa. Kot polnilo smo uporabili dolomitno moko. Ustreznost sveže injekcijske mešanice smo preverili na podlagi testov pretočnosti in izločanja vode. Izkazalo se je, da le apneno – cementni mešanici ustrezata kriterijema, pri ostalih pa smo imeli težavo s prekomernim izločanjem vode. V različnih časovnih obdobjih (35, 70 in 105 dni) smo na cilindričnih preizkušancih in standardnih prizmah izvajali preiskave strjenih injekcijskih mešanic. Prizme smo izpostavili različnim pogojem staranja na zraku, pri povišani temperaturi v NaOH raztopini in v zaprtih plastičnih posodah. Na osnovi rezultatov tlačne in upogibne trdnosti prizem smo sklepali, da se je razvila alkalno-karbonatna reakcija med dolomitnim polnilom in mineralnim vezivom na vzorcih izpostavljenih NaOH raztopini. Najvišje vrednosti tlačne in upogibne trdnosti smo dobili na apneno – cementnih vzorcih. Na valjih in prizmah smo s fenolftaleinskim testom spremljali stopnjo karbonatizacije, ki je bila najbolj intenzivna na prizmah. V jedru valjev je zaradi omejenega dotoka zraka za časa staranja preskušancev, potek karbonatizacije dolgotrajen. Dejstvo je, da pri injektiranju apnenih mešanic, le-te imajo pomanjkljivost počasnega strjevanja v zaprtih prostorih ter manjše trdnostne karakteristike v primerjavi s čistimi cementnimi mešanicami. V tem kontekstu, apneno-cementne mešanice imajo določeni potencial. Namen opravljenih raziskav je postaviti osnovo za nadaljnje raziskave apnenih injekcijskih mešanic na osnovi hidratiziranega apna in dolomitnega polnila.

• Language: Slovenian
• Keywords: gradbeništvo, magistrska dela, apnene injekcijske mešanice, injektiranje, dolomitna moka, preiskave injekcijskih mešanic
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: FGG - Faculty of Civil and Geodetic Engineering
• Place of publishing: Ljubljana
• Publisher: [K. Rojc]
• Year: 2015
• Number of pages: XVI, 83 str.
• PID: 20.500.12556/RUL-72273
• COBISS.SI-ID: 7156577
• Publication date in RUL: 10.09.2015

Secondary language

• Language: English
• Title: The preparation of injection grouts based on dolomite filler for stone masonry walls

Abstract

The objective of the presented master's thesis is the preparation of grout mixtures on the basis of dolomite filling with different mineral binders for the grouting of cultural and historic heritage buildings. Grout mixtures, which are compatible with the ingredients of existing stone walls of heritage objects were prepared and tested. The master's thesis serves experimental purposes and is fully based on different investigations of fresh and hardened injection mixtures on cylindrical test objects and standard prisms. The prepared grout mixtures were based on hydrated lime, lime with added tuff as well as lime and cement. Dolomite flour was used as filling material. The adequacy of the fresh injection mixture was tested according to flow properties and water release. It has been proven that only the lime and cement mixture conforms both criteria, whereas other mixtures showed excessive water release. Hardened injection mixtures were tested on cylindrical test objects and standard prisms in different time frames (35, 70 and 105 days). The prisms were exposed to different ageing conditions on air, at elevated temperature in the NaOH solution and in closed plastic containers. According to the results of compressive and tensile strength testing, it can be assumed that alkali-carbonate reaction developed between the dolomite filling and the mineral binder on test subjects exposed in the environment of NaOH solution. The highest levels of compressive and tensile strength were achieved using the lime-cement test objects. The phenolphthalein test on cylinders and prisms was used to determine the level of carbonization, which was the most intensive on prisms. Due to the limited air intake during the ageing of test specimens, the process of carbonization in the core of the cylinder is a long-term one. The fact is that when injecting the lime mixtures, their weak point is that the process of solidifying in closed spaces is slow and that their obtained strengths are lower compared to the pure cement mixtures. However, the lime-cement mixtures have a certain potential. The purpose of conducted research is to prepare the solid grounds for further research of lime injection mixtures on the basis of hydrated lime and dolomite filling.

• Keywords: civil engineering, master of science thesis, lime-based injection grouts, grouting, dolomite flour, tests of injection grouts