Abstract:

No. 1 Dayaoshan tunnel on WuhanGuangzhou passengerdedicated railway has the particularities of complex geological conditions, including karsts, fissures and karst caves. The tunnel has such features as large excavation crosssection, high waterproofing requirement and high quality requirement. The tunnel lining is required to have solid body and good appearance, without seepage, leakage, crack and wet stain on concrete surface. The author presents the construction methods of surrounding rock grouting, blind ditch installing, sidewall foundation treatment, geotextile placing, waterproofing membrane placing, drainage material installing, water stop tie installing, secondary lining casting and backfilling grouting on basis of the actual conditions. Owing to the great emphasis on the waterproofing of the primary reinforcement and the backfilling grouting after secondary lining, No. 1 Dayaoshan tunnel has reached the first class waterproofing requirement.

Key words: passengerdedicated railway, Dayaoshan tunnel, waterproofing and drainage, sidewall foundation, waterproofing membrane, drainage material, water stop tie, surrounding rock grouting