Jointless Asphalt Concrete Pavement Improvement on Elevated Highways to Enhance Smoothness: A Case Study of the Uttaraphimuk Elevated Road

Abstract

The Uttaraphimuk Elevated Tollway (Don Mueang Tollway) between Din Daeng and the Memorial Monument is a three-lane-per-direction elevated highway, approximately 21 kilometers long. The structure originally used 5 cm thick asphalt concrete with Asphaltic Plug Joints at 30-meter intervals, leading to unevenness in the riding surface. To address this, a seamless pavement system was piloted, reinforced with geotextile sheets.

Given the Don Mueang Tollway’s longer 30-meter Y-span structures and greater vibration compared to standard 20-meter spans, a trial section was implemented on the heavily loaded left lane. The 782-meter section was milled and repaved with Polymer Modified Bitumen 76 (PG76) mixed with 1/2” granite aggregate. Marshall Stability was approximately 4,140 lbs, with additional reinforcement provided by 420 g/sq.m paving fabric on a CRS-1P tack coat.

The resulting surface achieved improved smoothness, effective drainage, and reduced in-cabin noise by 4 decibels. After one year, no joint-related cracking was observed. Plans are underway to extend this technique to the center and right lanes.