Main Problems and Solutions on Design and Construction of Qinghai-Tibet DC Transmission Project in Permafrost Region

Abstract

The Qinghai-Tibet direct-current transmission project crosses the high-altitude permafrost region of the Qinghai-Tibet plateau. The permafrost foundation is characterized by being poor in thermal stability, rich in underground ice, very sensitive to climate warming, and strong in water-thermal activity. The foundation of the transmit electricity engineering therefore faces great challenges including tower foundation type selection and design, permafrost protection in the process of foundation construction and long-term stability. Based on an analysis of the geological engineering conditions and principal geological engineering problems of the project, a study is carried out on the design and construction problems of the transmission tower foundations in the permafrost region, the systematic analysis is also made regarding the main solutions to these problems with consideration of tower foundations long-term stability. This study will provide a theoretical basis and technical guide for design and construction of transmission lines in the permafrost region, and a reference for construction of transmission line projects in similar regions in China or even in the world.