Based On Sodium Bicarbonate And Aluminum Sulfate Foaming Agent Study On Properties Of Foamed Cement

China's existing construction area of 40 billion m²,the vast majority of energy-consuming buildings,and the new building nearly 2 billion m² each year,of which more than 95%is still a high-energy building.Huge building energy consumption,has become a huge burden of the national economy.Therefore,the construction industry overall energy-saving is imperative,foamed cement with its lightweight characteristics applied to high-rise building,the non load-bearing wall,greatly reducing the building energy consumption,but also reduce the high-rise building load,improve the stability of the foundation.At present,the foaming agent commonly used in foaming cement has some defects,which limits the spreading of foamed cement directly in the construction site.This paper uses sodium bicarbonate chemical foaming method,by changing the water/cement ratio,the amount of foam stabilizer and the curing condition,the foamed cement with different characteristics was used to test its apparent dry density,true density,water absorption rate,frost resistance,dry-wet cycling and sulfate-resisting resistance,According to the size of sectional area,the stomata are divided into three levels,the quantity,geometrical characteristics and distribution of stomata are measured by using image analysis method,the influence of various factors and pore structure characteristics on the physical properties of foamed cement is studied,and the following conclusions are obtained through orthogonal test:?1?When the water cement ratio is 0.75,the foamed cement has the smallest volumetric bibulous rate;When the water/cement ratio is 0.55,the foamed cement has the minimum quality bibulous rate,the best frost resistance,the wet-dry cycling performance and the sulfate-resisting property.?2?The change of the amount of foam stabilizer has great difference to the physical properties of foamed Cement:When the content of the foam stabilizer is 0.3%,the water absorption rate is the lowest,the moisture-wet cycling is the best,the foam-stabilizing agent is 1.2%,the frost resistance is the strongest,and the content is 0.9%,the sulfate-resisting is the strongest.?3?When the curing condition is the control variable,the curing condition of adding membrane humidification makes the foaming cement have the minimum water absorption rate and the freezing-thawing quality loss rate,while the foaming cement has better sulfate-resisting performance.The foam cement has the best frost resistance and wet-dry performance when the film is not wet curing condition.?4?When the D2 is 0.703mm,R is 1.057,the water absorption rate is the smallest;when the D1 is 0.216mm,the freezing-thawing strength loss rate and the quality loss rate are the smallest,and when the R2 is 1.036,the wet-dry strength coefficient is the largest,and when the R1 is 1.085,the compressive strength?5?When n is 33.778,s₃ is 0.272,the water absorption rate is the smallest,when the s₁ is 0.058,the s₂ is 0.083,the freezing-thawing quality and the strength loss are the smallest,and when the s₃ is 0.221,the coefficient of wet and dry strength is the biggest.?6?Through the orthogonal test,it is found that the water-cement ratio has the strongest influence on the properties of foamed cement,and the smaller water cement ratio is helpful to improve the frost resistance and corrosion resistance of foamed cement.In this paper,a composite silicate as a cementitious material,sodium bicarbonate and aluminum sulfate as foaming agent,through the chemical foaming method to successfully make foam cement,the existing chemical blowing agent added an option.At the same time,the regularity of the effect of water/cement ratio,foaming agent content,curing condition and pore characteristics caused by various factors on the durability of foamed cement is universal,which has a certain guiding function to improve the durability of foamed cement.