Deformation Characteristics of Crushed Rock-Soil Mixtures of Railway Subgrade under Train Cyclic Loadings

암과 흙 혼합재료로 이루어진 철도노반의 열차 반복하중 작용에 의한 변형특성

There are lots of tunnel intervals in the KTX II stage construction line for the linearity of railway line passing mountain region. In order to use the rocks from tunnel excavations, railway subgrades are constructed with crushed rock-soil mixtures. In this study, plain strain test using large scale box was conducted in order to analyze the characteristics of deformation behavior of railway subgrades composed of crushed rock-soil mixtures. The effects of variation of degree of saturation, stress level of applied loadings, and number of loading cycles on the resilient and permanent deformation behavior were analyzed. The results show that degree of saturation have a great effect on the deformation behavior of crushed rock-soil mixtures. The axial strain ranges between $0.1{\sim}0.8%$ with variation of degree of saturation, in assumption that deviatoric stress applied on the subgrade by high-speed train load is 55kPa.