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• In-situ high-speed train vibration measurements of pier and its surrounding sites. • The characteristics of vibration and distributions of deviatoric stress are analyzed by numerical calculation. • The relationships among peak vibration acceleration and distance from the pier in different seasons are obtained. • The relationship between permanent deformation, distance and time is obtained. Vibration induced by high-speed trains (HSTs) is well-known problem, which can deteriorate the embankments, piers and other structures along the railways. Particularly, the problem is more serious due to the freeze-thaw cycle of soil in seasonally frozen regions. In the present study, a series of field experiments are conducted to measure the HST-induced vibration of the pier and its surrounding different sites on the Harbin-Dalian high-speed railway (HSR) in seasonally frozen regions. The characteristics of the vibration in the time and frequency domains are analyzed based on the field measurement results. And the site effects are investigated by the frequency response function (FRF). In addition, the finite element model is established to study the vibration propagation characteristics along the soil surface and interior in different season by the analyzing the variation laws of acceleration peak (A max) and deviatoric stress (q d), and predict the permanent deformation (D p) of surface. The results show that the vibration characteristics of the pier and foundation sites are completely different. The A max decreases in the form of a power function with the distance (R) from the pier in the unfrozen and frozen conditions. Moreover, the distributions of the q d of soil surface in freezing season are obviously different from those in non-freezing season, but the difference between them decreases gradually with the increase of depth (D). The growth speed of D p decreases with the increase of the time, and the D p value will eventually trend to a stable value. [ABSTRACT FROM AUTHOR]

Rapid growth and implementation of high-speed trains (HSTs) have made commuting easier. However, the vibrations induced by HSTs deteriorate the embankment of ballastless tracks, particularly of those constructed in frozen regions. In this study, a series of field tests are conducted on the Harbin–Dalian high-speed railway in frozen regions to investigate the vertical acceleration (A z) at the embankment in terms of the train speed (v) and distance from the track centreline (d). The characteristics of A z in the time and frequency domains are analysed based on the field test results. The results show that A z under the unfrozen condition is greater than that in the frozen condition. The periodic excitation of the HSTs can be identified from the time histories of A z within the range of 13.2 m from the track centreline. Moreover, the frequencies of A z can be characterized by v and geometrical characteristics of the train, regardless of seasonal variations. The peak vertical acceleration (A p,z) and frequency-weighted vertical acceleration level (L az) are investigated with respect to v and d. In the unfrozen and frozen conditions, A p,z and L az decrease in the form of a power function with increasing d. The higher the v value, the higher the A p,z value. The dynamic impact coefficient of embankment is introduced to identify the A z performance. Some useful recommendations are provided, and the results can be used for validating numerical predictions related to HST-induced vibration. • Field test on embankment vibrations in unfrozen and frozen conditions due to China's high-speed trains are conducted. • Effects of seasonal variations and train speeds on time- and frequency-domain characteristics are analyzed. • The range on the dynamic impact coefficient in unfrozen and frozen conditions are compared. [ABSTRACT FROM AUTHOR]