The Design Principles of Embankment of Highway in Permafrost Regions and Their Application
DOU Ming jian,HU Chang shun (Chang′ an University, Xi′an Shaanxi 710064, China)
The design principles of embankment are an important basis for highway and railway engineering in permafrost regions. Using the general design principles of civil engineering for permafrost regions could lead to many severe problems presented owing to thawing and refreezing of embankment, such as thaw settlement, roadway cracking, foundation elevation, different deformation, slope slip and so on. Characteristics of linearity engineering and permafrost propose that the design principles of embankment in permafrost regions should consist with the section design principles and the site design principles, and various influential factors should also be considered in design stage. The division of the design principles should be from simple and rough outline to detailed and deeply, and the direction limits should be from line to point. First, on the basis of regional conditions determine the section design principles, and then on the basis of the characteristics of the structure and permafrost under the structure determine the site design principles. The section design principles are used for new project engineering and reconstruction project, and the linearity engineering in permafrost regions can be divided into protecting, simply protecting and no protecting the permafrost sections. In stage of the section design many influential factors should be considered, including geologic tectonics, geomorphologic patterns, annual mean air and ground temperatures, and permafrost table and so on. For site design stage the engineering type, ground ice content and soil type should also considered. According to the principles, the Qinghai-Tibetan Highway in permafrost regions is divided into sections; this division can be used in practice.
【CateGory Index】： U416.1