Effects of Vehicle Loads and Structure Combinations on Rutting Depth of Asphalt Pavements with Varied Base Layers in Toll Plazas

Asphalt pavements are increasingly used in toll plazas but may generate significant rutting depth due to unique load characteristics such as canalized traffic, slow vehicles, and frequent braking. Rutting factors of asphalt-paved toll plazas were analyzed by load, vehicle speed, base type, and thickness. 3D FEM simulations were performed for four base layer types by applying time-hardening creep modeling and equivalent temperature field in Changchun, China. Results show asphalt pavement rutting depth in toll plazas increases under combined action of slow vehicle speed, additional horizontal load, and weight. With 360 mm fixed base layer, rutting depth of flexible base is largest, followed by combined, rigid, and semi-rigid. Asphalt pavement rutting depths remain stable when rigid base exceeds 300 mm and semi-rigid exceeds 360 mm. Rutting depth of asphalt pavements with flexible or combined base exceeds those of semi-rigid and rigid base ranging from 180 to 360 mm but not when base layer exceeds 420 mm.