Study On Carbonization Resistance And Impermeability Of Recycled Micronized Concrete

With the development of China’s economy and technology,China has entered an era of rapid development.The following is the problem of waste disposal caused by the renovation or demolition of old buildings.If the waste is not treated,it will result in a huge waste of resources.Moreover,it is bound to affect the appearance of the city and cause pollution to the water source,soil and other environment.The disposal of construction waste is an urgent problem.The reuse technology of construction waste can not only achieve the purpose of saving resources,but also protect the environment,which is undoubtedly the most balanced solution.In the process of recycling construction waste,a large amount of recycled fine powder with a particle size of < 0.16 mm will be generated,which can be used as mineral admixture to replace cement to prepare concrete.This research use laboratory waste concrete preparation recycled fine powder with 0%,10%,20%,30% and 40% replacement ratio only mixed reclaimed powder or with the fly ash and silica fume mixed(RF(FA + SF)= 7:3,RF(FA + SF)= 5:5)concrete regeneration micro powder preparation,explore only mixed regeneration of micro powder and mixed mineral admixture between close packing effect on concrete compressive strength,carbonation depth,permeability grade,microstructure,etc.The results show that the compressive strength of the recycled fine concrete decrease with the increase of the amount of recycled fine powder.The compressive strength and carbonization depth of regenerated fine concrete were improved by the addition of regenerated micro,fly ash and silica fume.Secondly,it is found that the close stacking effect of mineral admixtures can reduce the harmful and multiple harmful holes in the recycled micro concrete and improve the impermeability of the recycled micro concrete.The maximum impermeability grade of recycled micro-powder concrete can reach P8.