Field measurement of strain response for typical asphalt pavement

Abstract

In order to reveal the changing law of the mechanical response of asphalt pavements under the action of vehicle load and provide references for the design of durable pavements, three typical asphalt pavement structures with flexible base (S1), combined base (S2), and semi-rigid base (S3) were selected to perform field strain tests under static and dynamic load using the fiber Bragg grating optical sensing technology. The changing characteristics of the strain field along the horizontal and depth directions of pavements were analyzed. The results indicate that the most unfavorable asphalt pavement layers were the upper-middle surface layer and the lower base layer. In addition, the most unfavorable loading positions on the surface layer and the base layer were the center of wheel load and the gap center between two wheels, respectively. The most unfavorable layer of the surface layers gradually moved from the lower layer to the upper layer with the increase of base layer modulus. The power function relationships between structural layer strain and vehicle speed were revealed. The semi-rigid base asphalt pavement was the most durable pavement type, since its strain value was the lowest compared to those of the other structures.

Optimal Decision Making for Polymer-Modified Bitumen Mixture Based on Fuzzy Comprehensive Evaluation

“…In this study, the analytic hierarchy process and EW methods were used together to calculate the weight. w (0) was calculated based on analytic hierarchy process, and w (1) was calculated based on EW. Then, the final weight can be obtained by Equation (8).…”

“…The weights calculated by the analytic hierarchy process method are listed in Table 10. According to the EW method, the entropy weights could be calculated, i.e., w (1) = [0.500, 0.236, 0.047, 0.106, 0.007, 0.002, 0.095, 0.006]. By using Equation (7), the final weights were obtained and they are listed in Table 11.…”

“…Bitumen pavement is a typical form of road pavement structure. With the continuous development of research methods, people have developed a clearer understanding of the internal stress and strain distribution law of the pavement structure under the influence of factors including environment and traffic [1][2][3][4][5], which makes it possible to design materials according to the stress characteristics and functions of pavements at different levels [6,7]. According to a large number of studies, including the analysis of pavement distress and mechanical analysis, it has been found that in the entire pavement structure, the rutting distress occurs mostly in the area 5-10 cm below the surface (the middle layer), especially under heavy-load and slow traffic [8][9][10][11][12].…”

Theoretical analysis on the measurement accuracy of embedded strain sensor in asphalt pavement dynamic response monitoring based on FEM

“…Requirement 2: Only materials with the same tensile stiffness can produce the same strain under the same external tensile force. As depicted in Figure 7c, the EM provided by the strain beam for the space occupied by the embedded stain sensor in the measurement direction should be the same as that of the asphalt mixture, which requires that the modulus of the strain beam should satisfy Equation (2).…”

“…Understanding the internal stress–strain state of pavement structure can guide pavement structure design and explain pavement failure mechanism 1–3 . Previous studies 4–6 demonstrated that horizontal tensile strain at the bottom of the asphalt layer was the primary contributor of bottom‐up fatigue cracking of pavement structure.…”