The Basics of Low Volume Weight Aerated Autoclaved Concrete Preparation

Abstract

This work deals with the basics and possibilities of preparation non-bearing, heat-insulating material based on autoclaved aerated concrete. The ultra-low volume weight (under 200 kg/m3) and sufficient compressive strength is achieved using standard industrial technology. The low volume weight and therefore low heat conductivity can be reached due to highly porous structure. Such a material can be prepared by foaming very fine material powder like silica fume and very finely ground sand. Unfortunately, foams consisting of fine inorganic hydrophilic particles are highly unstable. Therefore it is necessary to use an effective stabilization mechanism. In this work the stabilization mechanism is based on addition of small amount of water-soluble organic admixtures.

Design of the thermal insulation porous materials based on technogenic mineral fillers

“…Results of the studies by authors of [22,23] (on the ability of alkali-silicate systems with Al 2 O 3 to form insoluble products of Na 2 O·Al 2 O 3 ·2Si 2 O 3 ·nH 2 O in alkaline media) specify aluminum oxide of ash as a modifying component. It provides raw mixture with qualities required for the targeted product creation.…”

Preparation of Ultra-Low Volume Weight Autoclaved Aerated Concrete

“…Some basic characteristics of this material are summarized in Table 1. The aim of the present investigation and methodology setup follows our published results presented in [17]. Therefore, the experimental data from that study are not repeated in the present paper.…”

“…In our previous study [17] we investigated the influence of a substitution of ground quartz sand (S) by silica fume (SF) and the influence of specific surface s s of S used in the standard mixture mentioned above. Our goal was to prepare a material with final volume weight of approximately 120 kg•m -3 which was successful.…”

“…The standard raw materials used in this AAC technology study are the same as in studies [10] and [17]. Quartz sand has been used as the primary SiO 2 source.…”

“…We assume that such a difference has a negligible influence on the hydrothermal reaction mechanism. According to our previous study [17], the optimal surface area of the used S for achieving the highest ME value was calculated and such an S was prepared by grinding of raw sand in a ball mill. The calculation of the optimal specific surface area for a volume weight of 120 kg•m -3 was done by following empirical equation [17]:…”