Study on Thawing Settlement and its Influenced Factors of Embankment in Seasonal Frost Area

Abstract

Frost heaving and thawing settlement were the common diseases in seasonal frost area. In order to study the influenced factors of the subgrade thawing settlement, a series investigation were done on the subgrade of the Beijing-Baotou-Lanzhou railway line at the Chasuqi and Wulate qianqi sections from January to June. It was found that thawing settlement existed in embankment had great influence on the safety of subgrad running. This was less influenced by the even settlement, but was dangerous under the uneven state because of the track irregularity and its divorce from the ballast. The main factors affected the embankment thawing settlement included soil composition, water content and kind, environment temperature and the loading on soil. The larger thawing settlement would observed in the soil with large amount of silt particle, at the regions of low underground water level, with the kind of salt sensitive to frozen, at the atmosphere of the higher negative temperature sustaining a long time.