Experimental and analytical investigation on frost heave characteristics of coarse-grained soils under closed and open systems

Coarse-grained soil is widely used in the seasonal frozen region as subgrade filler. However, substantial frost heave has been observed coarse filler high-speed railway embankments. To investigate characteristics of coarse-grained a deep zone, indoor tests were carried out under water supply and no conditions. The effect water, fineness, temperature on behavior studied experimentally. relationship between freezing rate soils was analyzed. results show that process can be divided into rapid cooling stage, phase transition slow stability stage. In closed system, increase fine-grained does not affect process, while moisture content significantly affects whole process. opened both ambient When decreased from ?5°C to ?15°C, duration stage by almost 17 h, whereas when increased 2.7 16%, only 5 h. systems, development closely related Approximately 95% occurs during Frost develops most rapidly with approximately 85% amount occurring this