Performance Evaluation of Recycled Asphalt Mixtures Containing Construction and Demolition Waste Applicated as Pavement Base

Abstract EN

Construction and demolition waste contain large amount of concrete and bricks.

To identify its feasibility of applying in asphalt stabilized gravel mixtures as pavement base, this paper carried out researches on properties of recycled asphalt mixture (RAM) by laboratory testing, under different contents of recycled aggregates (RA) and proportions of bricks to concrete.

First, the basic physical properties of each component of the RAM were determined.

According to the actual screening passing rate, the Bailey method was used to design and verify the grading of RAM, and then initial asphalt content was estimated.

The stability, flow value, voidage, and bulk density were obtained by Marshall Test, and the optimal asphalt-aggregate ratios were determined under different RA contents and proportion of bricks to concrete.

Subsequently, the uniaxial compression test, splitting tensile test, immersion Marshall test, freeze-thaw splitting test, and Hamburg rutting test were performed to investigate mechanical properties, water stability, and high-temperature stability of RAM.

The results shows that as the content of RA increases from 0% to 100%, the corresponding compressive strength, resilient modulus, and splitting tensile strength all decrease; the same change trend is presented in the residual stability and freeze-thaw splitting test strength ratio and rutting depth.

According to the requirement of pavement base of high-grade roads in China’s standards, the recommended RA content and proportion of bricks to concrete were proposed for the design RAM.