Asphalt Concrete for High-Speed Railway Infrastructure and Performance Comparisons

Abstract

This paper presents the results of a laboratory investigation on the performances and mixture combination parameters of railway asphalt concrete (RAC) for supporting high-speed railway slab track. To apply the RAC effectively to high-speed railway infrastructures, modified highway asphalt pavement material tests are conducted to verify mixture parameters. A suitable gradation is recommended based on the test results. The air voids of the material RAC-25 used for railway infrastructure should be controlled from 1 to 3%. The results presented in the paper demonstrate that asphalt content can be determined based on modified mixture parameters. To verify the performance and analyze the mechanistic response of RAC infrastructure, full-scale laboratory dynamic models are established under different environmental temperatures and loading levels. Based on model testing, the reinforced RAC foundation with a 12 cm deep graded gravel layer replaced by RAC-25 shows much better performance compared with the traditional design.