The Identification and Classification of Freezing-Thawing and Frozen Environments for the Surrounding Rocks of Tunnels in Cold Regions
(1 Jiangsu Transportation Institute, Nanjing 210017; 2 Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000)
Abstract：
Aiming at the problems of classification and differences between freezing-thawing and frozen environments for the surrounding rock of tunnels in cold regions, this paper presents three control elements for the freezing phenomena of surrounding rocks (i.e., the freezing index, rock fissure water and rock freezing-thawing sensitivity). In light of different values of the freezing index and rock sensitivity to freezing-thawing, the surrounding rocks for tunnels in cold regions are divided into two categories: freezing-thawing surrounding rock and permafrost surrounding rock, which can be further divided into four subclasses according to freezing-thawing sensitivity, providing identification criterion for the freezing-thawing and frozen environments for surrounding rocks in cold regions. Based on this criterion, an analysis of the rock characteristics and the cause of rock problems was conducted regarding different tunnel surrounding rocks in cold regions, and precautionary measures and key research directions are put forward.
YUAN Yu-Lin-1,
Lai-Yuan-Ming-2
.The Identification and Classification of Freezing-Thawing and Frozen Environments for the Surrounding Rocks of Tunnels in Cold Regions[J] MODERN TUNNELLING TECHNOLOGY, 2016,V53(3): 19-25
2016, Vol. 53 