Study On Properties Of Waste Rubber Fly Ash Autoclaved Aerated Concrete

With the social progress and development,more and more people are paying attention on the building energy,and proposing new and higher requirements about wall reforming,and also providing a good opportunity for fly-ash autoclaved aerated concrete and other new wall materials' development.Under different production conditions,the steamed and aerated concrete shows the questions that easy shrinkage,density and heat preservation performance are substandard;This study draws lessons from the advantages of rubber concrete,added rubber particles to fly ash autoclaved aerated concrete to solve the questions.In this study,through changing addition and grain size of rubber particles and its steam autoclaved time and temperature then we used them to make orthogonal experiment to get the optimal ratio,we made research analysis to the influence significantly performance that the factors corresponding to,and made TG-DSC test to analyze the changing of rubber particles in aerated concrete under different autoclaved pressure and time,SEM-EDS and XRD tests to analyze aerated concrete under the different conditions.The optimum ratio is that the rubber addition is 4%,the autoclaved time is 6h,the rubber particle size is 200 mesh,the autoclaved temperature is 180?.With the increasing of rubber addition,the dry density of block decreased first and then increased,the compressive strength,flexural strength,freezing and thawing compression loss rate and the heat transfer were continues decrease,carbonation coefficient increases obviously,freezing and thawing loss ratio decreased first and then increased,water absorption rate increased constantly;and the smaller particle size of rubber,the greater moisture content of the block;With autoclaved temperature increasing,dry density and water content of steamed aerated concrete block decreased,compressive strength increased and the carbonation coefficient increased first and then decreased,freezing and thawing loss rate was reduced,freeze-thaw resistance increased;With autoclaved pressure time increasing,the compressive strength of the block increased reduction.The TG-DSC,SEM-EDS and XRD tests and analysis showed that the rubber particles had carbon loss in the autoclaved process,the same particle size rubber particle quality loss increased with autoclaved temperature rising and autoclaved time increase;The tightness of rubber particles and slurry interface decreased with the increase of autoclave time and temperature;The rubber particle size did not affect the formation of hydration products in slurry,the amount of rubber addition did not affect the formation amount of tobermorite in block,but it affected the C-S-H content in the product;With the increasing of autoclave temperature and time,formation amount of tobermorite increased and the C-S-H decreased slightly.