Qinghai-Xizang Railroad Construction in Permafrost Regions

Abstract

Construction of the Qinghai-Xizang Railroad (QXR) in permafrost regions presents a number of significant engineering problems. The engineering properties of permafrost can vary greatly, and climate warming, especially warm permafrost with high ice content, must be considered. Permafrost warming could induce ground ice thaw, producing embankment settlement. Consequently, thermal stability is a key consideration for the QXR construction in permafrost regions. In order to ensure permafrost thermal stability under the background of climate warming, ideas of embankment cooling to preventing permafrost change are proposed. Many methods of embankment cooling have been proposed to prevent the thawing of ground ice. For example, block-stone embankment, block and debris slope protected, thermosyphon, and special bridge designs. The amount of engineering practice and observational data testify that measurements of embankment cooling effectively decrease permafrost temperature and heighten the permafrost table beneath embankments.