Composition Design and Performance Evaluation of Foamed Asphalt Composite Cold Recycled Mixture
The optimum foaming conditions of foamed asphalt were determined by foaming test,and the optimum content of foamed asphalt with different mixing ratios of RAP and RAI was determined by Marshall test.Furthermore,the compressive strength,tensile strength,water stability and dy-namic modulus of foamed asphalt composite cold recycled mixture were tested and analyzed.The re-sults show that the foaming effect of asphalt is the best when the foaming temperature is 160℃ and the foaming water consumption is 2.9%.Under the optimal foaming conditions,the optimal content of foamed asphalt corresponding to the three schemes with 0%,20%and 40%RAP content is 3.4%,3.1%and 2.9%respectively.All three schemes have good compressive strength,tensile strength and water stability,and with the increase of RAP content in foamed asphalt cold recycled mixture,the de-gree of flexibility and tensile strength are gradually increased,but the compressive strength and water stability are reduced.
semi-rigid base asphalt pavementcomposite cold recyclingfoamed asphaltfoamed condi-tionpavement performance