Akytojo betono eksploatacinių savybių tyrimai

Abstract

Straipsnyje tiriamos UAB „Matuizų dujų silikato“ gamybos autoklavinio akytojo betono (AAC) savybės, įvertinant pasikeitimus EN standartuose bei AAC struktūros ypatumus. Ištirta, kad smulkiagrūdė, uždarų porų 400–600 kg/m3 tankio AAC struktūra užtikrina žemas šilumos laidžio (l10 = 0,11-0,17 W/m×K), vandens garų difuzijos (m = 4,9-6,1) ir sorbcinio drėgnio (esant aplinkos santykiniam drėgniui 97 % WS = 4,0-5,6 %) vertes. Nustatyta, kad 500 kg/m3 tankio 2,5 stiprio klasės AAC blokelių, sujungtų plonu mūro skiedinio M5 sluoksniu, charakteristinis pradinis stipris kerpant yra 0,22 N/mm2 ir atitinka STR 05.09:2005 reglamento reikalavimus.

The LST EN 771 standard of masonry article and maintenance characteristics determination will come into force on June 1, 2006 in Lithuania and will allow evaluation of the effect of masonry elements (ceramic, silicate, concrete, autoclave porous concrete as well as natural and artifical stone) and joining bond (mortar) on masonry properties. The aim of this work was to investigate the properties of autoclave porous concrete (AAC) blocks (density 400 kg/m3 to 650 kg/m3) by manufactured JSC „Matuiz4 dujq silikatas" in accordance with the requirements of the new standard. The AAC specimen structure was found to have a fine porous structure in 0.1 mm to 1 mm diameter. Such a specific structure determines the material's properties. This was also confirmed by the AAC block heat conductivity coefficient (A,o) and the material's strength properties (evaluating the new growths formed during autoclave treatment and their crystallization degree). The A,o was found to depend on the density and to equal 0.107 W/m•K to 0. 157 W/m•K. The other AAC properties such as water vapour permeability, sorption humidity, shrinkage on drying helped to evaluate the masonry maintenance characteristics that ensure the necessary microclimate of the premises. The water vapour specific resistance depended on AAC density and varied from 3.17.10'" kg/m•s•Pa to 4.00.10-" kg/m•s•Pa, while the sorption humidity depended on the relative air humidity and specimen density (from 1.06% to 5.6%). The mortar initial shear strength that joined the AAC elements reached 0.22 N/mm2.