Anti-freezing through Drainage Ensured by Heating with Double Thermal Resources for Construction Joints of Tunnels in Cold Area

摘要

A new anti-freezing method for construction joints in tunnels is put forward through effective drainage ensured by heating with warm air or ribbon heater. The heating system is intelligently controlled according to the monitoring and analysis of the surface temperature of the secondary lining. This method is characterized as the following: (1) preventing leakage without pressure increase is realized through effective drainage at the back of secondary lining with special drainable channels;(2) alternative heating resources including warm air and electrical energy are offered to heat the region around construction joints, which can prevent the drainable channels from freezing and jamming;(3) for efficient and economy purpose, heating can be carried discontinuously as well as partly at circumferential and longitudinal direction. Numerical simulations validate the availability of heating method for anti-freezing.