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Coupled effects of railway vibration,rainfall,and drying-wetting cycles contribute to new types of loess disasters such as the collapse and vibration-induced settlement of the railway subgrade,loess mass disintegration,and slope sliding,during the large-scale construction and operation of high-speed or heavy-haul railways in China.This has significant consequences for railways that require millimetre-level deformation control,seriously threatening railway operation and people's lives.Therefore,for the first time,“five vibration-induced effects” on loess subjected to vibration,water immersion,and drywetting cycles are discussed including the vibration-induced acceleration of cracking,infiltration,disintegration,sliding,and subsidence.In this paper,the vibration-induced acceleration of infiltration is discussed mainly.The response of loess to locomotive vibration along railways was determined using field sampling and data processing.The dominant frequency of locomotive vibration are 18-22 Hz and the maximum amplitude is 0.4 mm.Tests regarding the vibration-induced acceleration of the permeability were conducted on intact loess using a newly developed vibration permeability apparatus.The results reveal that the vibration accelerates the water permeability and increases the water saturation of loess.The permeability coefficient of saturated loess under vibration is ~1.5-20 times of that without vibration,reaching a maximum at a vibration frequency of 20 Hz.Vibration-induced infiltration tests were carried out on a loess column and the vibration-induced acceleration of water infiltration,wetting front evolution,and air outflow were analysed.The vibration-induced acceleration of infiltration strongly depends on the dry density,vibration frequency,and vibration amplitude.This pioneering work explores the mechnism of loess disasters triggered by locomotive vibration,rainfall,and drying-wetting cycles.