Case Study: Ten Year Field Performance Evaluation of Flexible Base Asphalt Pavement Design in Heavy Load Condition

Abstract

This research aims to evaluate the performance of flexible base asphalt pavement compared with traditional semirigid base asphalt pavement in practical application in central China under heavy load conditions. Four different flexible base structures were constructed in the field, and the material design and performance test of flexible base asphalt pavement were carried out. The experimental section was built on a highway in Henan Province with semirigid base asphalt pavement in the main-line, and the performance was evaluated by follow-up tracking and observation. Through 10 years (2009–2018) of field performance observations, a total of five indexes of pavement performance [International Roughness Index (IRI), Rutting Depth Index (RDI), Skid Resistance Index (SRI), Pavement Structural Strength Index (PSSI), and Pavement Condition Index (PCI)] were collected. The results show that the IRI was not sensitive to the base structure but the PSSI and PCI were greatly impacted by the strength of the base structure; the result found that proper designed flexible base asphalt pavement using AH-30 asphalt with four different structural types had better or comparable performance over traditional used semirigid base asphalt pavement in terms of temperature stability, crack reduction, and fatigue resistance under the heavy loaded conditions. This research suggested designing a layer of stabilized macadam or ATB at the base to improve the overall strength and performance of the structure.