Abstract:

On basis of the construction of the ultrashallowburied portion of Kunlunshan tunnel of Qingzang railway (from DK977+600 to DK977+660), the article describes the effects of the following measures in the tunnel construction: surface consolidation grouting, freezing/thawing prevention by means of sun shading, pregrouting by means of small pipes installed around the tunnel arch, weak blasting, shotcreting and monitoring. Furthermore, the article also describes the freezing/thawing prevention construction techniques, the waterproofing and drainage construction techniques and the technique of thermal rods as specially taken to consolidate the freezing ground.