Research on Adaptability of Secondary Recycling Materials Using in Asphalt Pavement Structures

Many roads that have been reconstructed with cold recycling technology have shown signs of pavement distress after long-term usage. Some roads in this condition can be reconstructed with secondary recycling technology. The unconfined compressive strength and the modulus of elasticity of the cement's secondary recycling materials were obtained by laboratory testing. The results indicate that the strength is lower than ordinary base materials stabilized by cement, and that the temperature exerts a tremendous influence on compressive strength. The stress characteristics of two typical secondary recycling asphalt pavements are analyzed using Bisar3. The results show that the tensile stress at the bottom layers is quite different when the secondary recycling materials are used in the base or subbase. When secondary recycling materials are used in the subbase, the modulus should not be very high. When secondary recycling materials are used in the base, it must be verified that the subbase is in good condition and has enough bearing capacity.