Dynamic Features of Low Embankment Subgrade on Expressways Under Traffic‐Induced Loads: Experimental and Numerical Study

The dynamic features of the subgrade are closely related to vehicle operation safety. Most of the previous studies are limited to the dynamic response of high embankments, therefore, in this study, the dynamic characteristics of low embankment subgrade under dynamic traffic loads are investigated through field tests and numerical simulations. Furthermore, the impact of the combined influence of rainfall and traffic load on the dynamic strength of the subgrade was explored. The results indicate that, compared to light vehicles with an axle load of less than 5 tons, the dynamic stress, acceleration, and dynamic displacement of oversized vehicles with an axle load of 20 tons increased by 7–10 times, 1.1–1.6 times, and 1.3 times, respectively. In a rain‐infiltration environment, compared to the dry state, the dynamic stress of the subgrade bed increased by 1.04–1.26 times when the vehicle speed was 80 km/h and the axle load was 20 tons. This work provides a theoretical basis for the reconstruction and maintenance of low embankment subgrade.