Study On The Modified Thermal Insulation Mortar System Based On The Reuse Of Foam Concrete Slab Waste Resource

With the continuous development of society and economy,the needs and demands for building energy efficiency in China are continuously improving.Building energy conservation is mainly achieved through the wall heat insulation material system.The reason why vitrified microsphere thermal insulation mortar is an ideal thermal insulation materialfor exterior thermal insulation material is that it not only overcomes the disadvantages that the expanded perlite has high water absorption,easy powdering and large vol?me shrinkage,but also makes up the defects of poor fire resistance of polyphenylene organic material,producing harmful gases at high temperatures,poor aging and weather resistance.This paper takes the foamed concrete slag waste modified insulation mortar as research object to develop appropriate technical route that taking a large n?mber of discarded bits and pieces which are produced in the foam concrete cutting processas cement material to substitute for fly ash mixing into ordinary vitrified microsphere thermal insulation mortar.And then through theoreticalanalysis and experimental research,prepare modified insulating mortar,study its thermal insulation properties,physical and mechanical properties,and eventually,realize the recycling and utilization of FC slag waste while satisfying all the properties of the thermal insulation mortar.Through the experimental study,we found that properties of thermal conductivity,dry density,compressive strength and linear shrinkage rate can meet the standard requirements when using FC slag waste to replace waste fly ash slurry;While the amount of substitution exceeds 75%,the tensile bond strength and frost resistance are no longer in line with the requirements.Hence,when the proportion of FC slag waste replacement is not more than 75%of the mass percentage of fly ash,it can meet the requirements of the specifications.we also concluded that compressive strength,tensile bond strength and shrinkage of mortarhe would decrease as the increase of fineness of FC waste;When the density of vitrified microsphere is small,the modified insulation mortar has low strength and can not meet the requirements of the standard;while the thermal conductivity and dry density of the modified insulation mortar would be too large if the density is large.Through synthetical consideration,the modified insulation mortar with optim?m performance can be obtained on the condition that the FC slag waste with particle size of about 133 ?m replacing 75%fly ash is added to the vitrified microsphere thermal insulation mortar whose aggregate is two grades of vitrifiedmicrosphere.