The purpose of asphalt pavement structural design is to get a materially-coordinated and structurally-durable product, and a pavement structure with good road performance by combining the structural layer materials reasonably. However, due to lack of a rational evaluation index on the parameter combinations of structural layer materials, the structural layer materials are poor in terms of coordination, have low efficiency, and the actual use period is much lower than the designed working life. Therefore, it is very important to conduct research evaluating the coordination of the structural layer materials. In this study, the sensitivity of mechanical parameters and equivalent envelope area are proposed as new indexes to evaluate the coordination of material design of asphalt pavement structure layers. Software is developed to calculate the equivalent envelope area that can quantitatively evaluate the coordination among different layers and visualize the mechanical transfer behavior of each structural layer. Based on the equivalent envelope area index, this study incorporates two new steps in the design of pavements, namely the structural form comparison and optimization, and proposes a new structural design process. Finally, the rationality and reliability of the equivalent envelope area index are verified by presenting fatigue life calculation and field verification in a test road. The results propose a clear evaluation index of the coordination of material design of each structural layer, which makes the structural design of the asphalt pavement more scientific and reasonable.

https://www.mdpi.com/2076-3417/10/9/3178/pdf

Evaluation of the Coordination of Structural Layers in the Design of Asphalt Pavement

Semi-rigid asphalt pavement, compound base asphalt pavement and flexible base asphalt pavement are three main structures in China. Each asphalt pavement differs at the structure of base. In order to further analyze the stress characteristic, the paper took base as the starting point of study, set interlayer binding condition as not fully continuous and considered the horizontal load and vertical load under heavy load combining with our national, then made calculation in the full thickness range of pavement with the use of shell designing software Bisar3.0, so the worst distribution area for three kinds of asphalt pavement were obtained. The results showed that discontinuous interlayer binding condition made flexible strain and flexible stress show discontinuous distribution during structure height; the maximum flexible strain all appeared on the bottom of surface layer for three kinds of asphalt pavement, while the maximum flexible stress appeared in different structure layer; impose of double-double made shear stress on the surface of pavement stand greatly high degree; asphalt stabilized crushed stone of compound pavement must be designed to both anti-fatigue and anti-reflection crack; it’s suggested that designed indexes matching mechanical destroy mode should be chosen to guide pavement design.

Yan-hong Zhang

Papers

Analysis on Mechanical Response for Three Kinds of Asphalt Pavement Under Discontinuous Interlayer Condition