Strengthen Treatment Of Recycled Aggregates And Application Research Used In Asphalt Stabilized Macadam

Because of the formation of micro cracks and the effect of impurities such as cementmortar, recycled aggregates is showed in the test result that it has more disadvantages such aslow strength, high absorbing water rate, porosity and water absorption and small density. So itcan only be used in the cement and concrete pavement concrete of low intensity, rarely inasphalt mixture.Through the detection of crushing value, abrasion value, water absorption, bulk density,apparent density of recycled aggregate of construction waste and other basic performanceindex, analyses the main differences of the characters between recycled aggregate and naturalaggregate and identify the key issues of construction waste for being used in asphalt mixture.The three kinds of solution of sodium silicate solution, silicone resin and organic silanecoupling agent (KH560) are selected to strengthen recycled aggregate. Orthogonal experimentis used to determine the optimal concentration of sodium silicate solution.，temperature ofprocessing of recycled aggregate and other test conditions. The best treatment method isdetermined by using different dosage and different water oil ratio (the proportion of water andorganic silicon resin) of organic silicon resin. And determine the silage coupling agenttreatment effect to recycled aggregates. This paper analyses the effect by scanning electronmicroscopy (SEM).Because of large aggregate porosity and high bibulous rate, the mix proportion design ofrecycled aggregates has big difference from natural aggregate. The differences of recycledaggregate and natural aggregate in the mix proportion design of asphalt stabilized macadam(ATB–25) have being studied. The determination method of key parameters such astheoretical maximum density, bulk specific gravity are proposed, and confirm the mixtureratio design method of recycled aggregate and attention points.Recycled aggregate modified by organic silicon resin and not modified is selected tomake the mix design of asphalt mixture and verify the effect of the processing and thefeasibility of the design method through comparison and analysis of road performance.