Papers by Andreja Padovnik
Sustainability
Organic additives from plant and animal extracts were commonly used in lime mortar in the past to... more Organic additives from plant and animal extracts were commonly used in lime mortar in the past to improve and modify its properties. In modern times, they have been replaced by inorganic additives. The objective of this research is to investigate the influence of fish animal glue and the role of the filler particle size distribution on the fresh and hardened properties and durability of lime grouts. Wet density, water retention, fluidity, and injectability were tested in the fresh state. It was found that the particle size distribution of the selected filler, which can increase the packing density of the solid particles of the grout, and the W/B ratio have a great influence on water retention and fluidity. In the hardened state, porosity and compressive and splitting tensile strength were evaluated on 90-day- and 365-day-old specimens. The presence of animal glue improved the mechanical properties, due to a higher carbonation rate. The combination of the two fillers that resulted in...
Materials, 2021
Dry hydrated lime is an air binder often used in architectural injection grouts. This study compa... more Dry hydrated lime is an air binder often used in architectural injection grouts. This study compared the influences of three commercially available dry hydrated limes on the injection grouts’ workability and mechanical properties. The main differences between the limes were in their chemical and mineralogical composition and Blaine specific surface area. The grouts were composed of dry hydrated lime, finely ground limestone filler, water, and super plasticiser. Subsequent results obtained revealed that the Blaine specific surface area is not directly related to the fresh grout properties. Grain size distribution and shape of lime particles and their aggregates in the water suspension are key parameters influencing the following fresh grout properties: fluidity, injectability, the mixture’s stability, and water retention capacity. However, the lime injection grouts’ mechanical strengths were higher in relation to an increase in the content of portlandite and the Blaine specific surfa...
Materials, 2020
Injection-grout density is an important parameter when its additional weight leads to consolidate... more Injection-grout density is an important parameter when its additional weight leads to consolidated decorative plasters becoming damaged. This is especially evident in larger detached areas. In this study, thin-walled soda–lime–borosilicate glass microspheres were used as a density-reducing constituent in hydrated lime grout mixtures. The normal density grout composition—one volume part hydrated lime and three volume parts inert limestone filler with 0.5% of the polycarboxylate ether-based superplasticiser—was modified with partial substitution of the limestone filler with lightweight glass microspheres. The following volumetric proportions between limestone filler and glass microspheres were used: 100%:0%, 67%:33%, 50%:50%, 33%:67%, and 0%:100%. With the increase of the glass microspheres’ volume, the density of the grout is gradually reduced. Furthermore, there is a decrease in the stability and injectability of fresh grout. In its hardened state, the grout’s strength again reduces...
Construction and Building Materials, 2020
h i g h l i g h t s Combined lime-cement structural injection grouts were designed. Time evolutio... more h i g h l i g h t s Combined lime-cement structural injection grouts were designed. Time evolution of the grout setting process was monitored by proton NMR spectroscopy. The grout setting process is significantly slowed down relative to the cement pastes. Compressive strengths of the grouts are appropriate for historical buildings repair. Swelling agent lowers the compressive strength of the grouts to an unacceptable level.
International Journal of Architectural Heritage, 2016
ABSTRACT In the described studies with the aim of optimizing hydrated lime grout composition, the... more ABSTRACT In the described studies with the aim of optimizing hydrated lime grout composition, the first measure was to reduce the water content of the grout using a highly efficient polycarboxylate ether-based superplasticizer, whereas the second measure was to increase the content of the inert limestone filler with an adequate grain size distribution. In this way, an attempt was made to achieve the best possible volume stability and strength properties of the hydrated lime grout, while continuing to fulfill the other necessary requirements regarding non-structural grouting works which are reported in the literature. The results of the tests showed that a non-structural grout consisting of 1 volume part of hydrated lime CL 90-S and 3 volume parts of inert limestone filler, with 0.5% of the polycarboxylate ether based superplasticizer, fulfilled most of the established requirements, so that it is thus potentially suitable for re-attachment interventions on architectural surfaces.
Materials and Structures, Dec 20, 2022
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Papers by Andreja Padovnik