Establishment and verification of different fixed parameter combinations of the 2S2P1D model for asphalt mixture

作者：Han, Ding^*; Zhu, Chaochao; Du, Qingcan; Hu, Huimin

来源：CONSTRUCTION AND BUILDING MATERIALS, 2022, 345: 128379.

DOI：10.1016/j.conbuildmat.2022.128379

• Asphalt mixture
• Master curve
• Shift factor
• Sensitivity
• Fixed combination
• Randomness

In order to analyze the simplification possibility of the 2S2P1D model in constructing the master curve of asphalt mixture, the fixed combinations of parameters in {E0, E infinity, delta, k, h, beta, tau ref} are proposed, evaluated and applied. By establishing a method of parameter sensitivity, the sensitivity classification of parameters for asphalt mixture using the 2S2P1D model is implemented. Then, the fixed value of each parameter in {delta, k, h, beta, tau ref} for asphalt mixture is obtained by a method of fixed parameter analysis. During these analyses, different shift factors and fitting functions using different types of test data are used to analyze the differences in constructing the master curve of asphalt mixture. The results show that each parameter in {k, h, beta} that has weak sensitivity for the 2S2P1D model can be determined for different types of asphalt mixtures. Comprehensive consideration changes of the goodness of fit and the shape of master curves of various moduli, the fixed combination of material pa-rameters Fix_beta-k-h-delta or Fix_beta-k-h-delta-tau ref is recommended to be used in combination with the shift factor WLF. Based on fixing some parameters of the 2S2P1D model, analyzing the fitting values of unfixed parameters for different types of asphalt mixtures can better compare the differences and statistical randomness, and these material features can be used in the future structural response analysis.