Experimental Study On Wear Resistance Of Recycled Aggregate Concrete

Recycled aggregate concrete is a kind of special concrete with high porosity and high permeability,which is made from natural aggregates by using the recycled aggregate of construction waste.The application of reclaimed water concrete can not only solve the environmental problems caused by construction waste,save energy,but also use the advantages of permeable concrete.However,compared with ordinary concrete,the wear-resisting property of recycled permeable concrete is poor,which seriously restricts the extension and application of recycled permeable concrete.It is of great significance to study the wear-resisting property of recycled concrete and further expand the scope of reuse of abandoned concrete.Based on a large number of literatures at home and abroad,this paper studies the wear-resisting property of recycled concrete from several aspects.Article first has carried on the exploration to the basic properties of recycled aggregates,and starting from the raw material,permeable concrete recycled aggregates is analyzed the influence factors of wear resistance and impact mechanism of the natural defects in view of the natural aggregate,proposed adding fly ash,silicon powder,powder and fiber such as measures to improve the wear resistance of the permeable concrete recycled aggregates,the main research conclusions are as follows:(1)Compared with natural aggregate recycled aggregates,the bibulous rate is fast,density is small,large void ratio,low robustness,high silt content and crush index,but compared to standard GB/T 25177-2010 rules in the use of recycled coarse aggregate concrete,the test using recycled aggregates meet basically the requirements.(2)Study the factors influencing the wear resistance of recycled aggregate concrete and its laws.When the replacement rate of recycled aggregate was 50%,the wear rate was the lowest.There is a negative correlation between the size of water glue ratio and the wear resistance of recycled concrete.5% volume sand rate has the minimum wear rate and the best wear resistance;When the proportion of grade is 1:2,the wear resistance is the best.(3)Aiming at the natural defects of natural aggregates,this paper puts forward a way to improve the wear-resisting property of recycled permeable concrete.The wear-resistance of recycled concrete 28 d decreases with the increase of fly ash content.With the increasing of the substitution rate of silica powder,the wear-resisting loss rate of recycled aggregate concrete is increasing.The wear-resisting property of concrete can be improved by replacing 10% of cement with 15% and 20% recycled micro-powder.The wear rate was reduced by 10.77% and 15.18% respectively by using the method of premix and cement.