Aerated Concrete Performance Test Research

At present,the construction industry has been restricted by such problems as environmental protection and sustainable development,autoclaved aerated concrete began to be widely concerned.Autoclaved aerated concrete belong to the new type of multi-functional environment-friendly building materials,it has light weight,low thermal conductivity,sound absorption,sound insulation effect is good,strong earthquake fire and advantages of the construction is convenient,to save energy and protect the environment is good.But the autoclaved aerated concrete in use process will appear empty drum and crack,fall off,or is the quality problem,such as leakage for the sensory quality and function of the building is extremely unfavorable.Therefore,the systematic study on the performance characteristics of the aerated concrete,solve the problem of construction technology and quality control.At present,the construction industry has been restricted by such problems as environmental protection and sustainable development,autoclaved aerated concrete began to be widely concerned.Autoclaved aerated concrete belong to the new type of multi-functional environment-friendly building materials,it has light weight,low thermal conductivity,sound absorption,sound insulation effect is good,strong earthquake fire and advantages of the construction is convenient,to save energy and protect the environment is good.But the autoclaved aerated concrete in use process will appear empty drum and crack,fall off,or is the quality problem,such as leakage for the sensory quality and function of the building is extremely unfavorable.Therefore,the systematic study on the performance characteristics of the aerated concrete,solve the problem of construction technology and quality control.This paper studies the porosity and pore structure,moisture content,the influence of the expansion direction of aerated concrete strength;Apparent density and moisture content of aerated concrete;the influence of thermal conductivityOptimize the mixture ratio of aerated concrete matrix,and study the different ways of air-entraining and mixed abhorred in water effect on the properties of aerated concrete;Finally,in the aerated concrete factory lab to get the optimal mixture ratio to pilot production,and test the performance.The results show that:(1)with the increase of porosity,apparent density of aerated concrete and compressive strength are presented to reduce trend;With the increase of moisture content,compressive strength of aerated concrete presents a lower trend,when the moisture content is between 25%-25%of aerated concrete,small variations in the compressive strength of aerated concrete;Aerated concrete has the characteristics of anisotropy,aerated concrete parallel to the direction of the gas force when the compressive strength of is perpendicular to the direction of the gas force when the compressive strength of 78%;(2)with aerated concrete apparent density increase,its own air content showed a trend of decline,and presents the trend of increased thermal conductivity;As the moisture content increased,the coefficient of thermal conductivity of aerated concrete shows the tendency of increase gradually.By comparing with different materials,the coefficient of thermal conductivity of aerated concrete,lowest 0.21 W/(m·K),the highest thermal inertia index,at 3.81,shows that aerated concrete in the thermal insulation performance of several kinds of materials,the best;(3)to the calcium silicon ratio(C/S),sulfur,aluminum ratio(S/A),calcium aluminum ratio(C/A)as A parameter to deterrmine the optimal mixture ratio of the aerated concrete matrix,and C/S = 0.52,S/A = 0.16,C/A = 1.7,water is more than 0.6,the aluminum content is determined to be 1.0 ‰～1.4 ‰,the dosage of water reducing agent for gelled material of 0.9 per thousand;(4)with the method of composite air-entraining,can to a certain extent,improve the performance of aerated concrete,optimization of pore structure;After test showed that the aluminium powder-ferrosilicon alloy powder composite air-entraining,aerated concrete hole is the smallest,hole the most dense and uniform,the distribution of hole wall is thinner than the other two kinds of air-entraining way;(5)in the mixed abhorred agent,not harmful to the strength of the aerated concrete;Hatred in mixing water can be appropriately raise the dry-wet circulation coefficient of aerated concrete,reduce the water absorption of concrete,improve concrete freezing-thawing resisting performance,the study found that the composite air-entraining way,the way of water in mixing abhorred,the preparation of aerated concrete frost resistance can meet the standard in the cold region for aerated concrete freezing-thawing resisting cycle requirements;Factory production and the performance of aerated concrete and laboratory preparation,there were no significant differences of aerated concrete and water absorption were not more than 40.0%,coefficient of dry-wet circulation were greater than 0.9,the frost resistance to meet the requirements of the standard.