Research On Properties Of Areated Concrete Masonry In Cold Regions

In the current world, energy shortages and sustainable development need to beworked together to face the important issues, energy saving is critical to nationaldevelopment. At present, energy conservation of the building is listed as a key of theenergy saving field, countries have strengthened building energy efficiency standards inrecent years. Energy conservation of the wall is an important content of building energyconservation, in the north cold region, energy consumption of heating is large in winter,therefore, the development and promotion of aerated concrete energy-saving wall isgreat significance for the outer wall energy saving in the north cold region.At the moment, aerated concrete haven’t been promoted and used widely in thenorth cold region. Many problems exist in the use of aerated concrete such as wall crack.In this paper, changing the bleed way is used to analyze its influence of aerated concreteblock’s strength and dry density. Finally, aluminum content is0.07%by singlealuminum powder bleed way, entraining agent is1/5of the amount of aluminumpowder content by compound bleed way, and the silicon iron alloy powder content is1/5-1/6of the amount of the aluminium powder content. Using expanded perlite as fineaggregate, adjust the dose of cementing materials and the replacement of fly ash cementpreparation for aerated concrete masonry insulation mortar. The final parameter ofcement with coal ash, expanded perlite, redispersible powder, cellulose ether, airentraining agent and water reducing agent is1:0.5:0.02:0.001:0.0002:0.003.Theperformance indicators of mortar are: consistency is96mm,separation is12mm,compressive strength is6.39MPa, bonding strength is0.34MPa,contract value is0.97mm/m, thermal conductivity is0.1242W/m·K. All of above content satisfy thestandard for special aerated concrete masonry mortar.Using B05fly ash aerated concrete block and unifying mortar joint thickness,measure compressive strength, axial deformation and the joint shear strength ofdifferent block which are made with special insulating masonry mortar and normalcement mortar masonry aerated concrete masonry respectively. Results show that bothcracking strength and compressive strength of the thin seam ash masonry are higherthan that of thick ash brick masonry, while the shear strength showed oppositeregularity. With the same mortar joint thickness, compressive strength and shearstrength of special insulating masonry mortar block are higher than that of normalmortar masonry block. Furthermore, the utilization rate of special insulating masonrymortar block is higher than that of normal mortar masonry block, which is66%.Finally, aerated concrete walls that length is2m and height is1.25m arerespectively arranged under outdoor natural environment and room temperatureenvironment. Micrometers are fixed up in order to measure wall contraction, while temperature sensor are arranged in outdoor masonry wall in order to analyze the wallheat preservation effect comparing with autoclaved fly ash brick wall.The result shows that, the wall contraction of upper part is greater than that oflower part. When the temperature changes sharply, the wall contraction is much biggerthan normal. Contraction of the natural outdoor wall is higher than the condition ofindoor environment wall. In the same condition, as inner surface average temperature ofaerated concrete wall which is8.6℃is higher than that of autoclaved fly ash brick wall,aerated concrete wall has good heat preservation effect to be used as the energy savingwall.