Abstract
Substantial frost heave has been observed in coarse fills in high-speed railway embankments. These coarse fills have low fine contents and very low water content. The groundwater table is located below the coarse fills. The coarse fills were considered not susceptible to frost heave. Recent experimental results in the literature showed that vapour transfer has a considerable influence on the frost heaving of unsaturated coarse-grained soil. But vapour transfer has been rarely considered in the modelling of frost heave. This study presents a new frost heave model with considering vapour transfer and its contribution to ice formation. The rigid ice theory is applied to initiate an ice lens formation in the frozen fringe. An updated computer programme PCHeave is developed by considering the vapour transfer. The results of the proposed model are compared with laboratory test results, which show reasonable agreement. The prediction of the model agrees well with the measured frost heave and frost depth, which indicates that the proposed model can reasonably reflects the process of frost heave in unsaturated coarse soil.
Highlights
In seasonally frozen soil areas, the effects of frost heave on high-speed railways are significant because of stringent deformation requirement of truck foundation
The Harbin-Dalian Passenger Dedicated Railway is the first dedicated passenger line in the world to operate in cold regions. These coarse fills for high-speed railways, classified as Group A and Group B in the Chinese standard, have low fines contents and very low initial water content
The coarse fills were considered not susceptible to frost heave, but substantial frost heave has been observed in the coarse fills in high-speed railway embankments [1,2,3,4]
Summary
In seasonally frozen soil areas, the effects of frost heave on high-speed railways are significant because of stringent deformation requirement of truck foundation. In all the models and theories discussed above, including the more recent premelted ice model, frost heave is considered to be a consequence of freezing and migration of liquid water in fine grained soil. Teng et al performed a series of laboratory tests to investigate the factors that will affect vapour transfer in a clean sand, including initial water content, dry density, boundary temperature, and water supply pattern [18]. They found that vapour transfer can be the primary mechanism of moisture migration in coarse-grained soil, especially when the initial water contents of the soils are low. The significance of vapour transfer in coarse-grained soils is analysed based on the proposed model, and some concluding remarks are summarized
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
