Investigation shows that
highway tunnels in cold regions have severe freezing-induced damages, which affect
the safety of the tunnel structure and the tunnel operation seriously. In this
study, the freezing-induced damages of tunnels in cold
regions, as well as the causes for the damages, are discussed, the concept and
approach for the anti-freezing design of the tunnels
are summarized, and the calculation methods for the anti-freezing fortification length, the calculation methods for the frost
heaving forces, and the status and effect of the application of the anti-freezing measures for tunnels in cold regions are analyzed.
Conclusions drawn are as follows: (1) The design concept that "freezing
prevention shall be taken as the main measure, frost heaving force resistance
shall be taken as the supplementary measure, and the freezing prevention
measures and the frost heaving force resistance measures shall be
coordinated" shall be adopted for the anti-freezing
of tunnels in cold regions. (2) For highway tunnels in cold regions where the
groundwater is developed, graded anti-freezing should
be designed according to the average temperature in the coldest month. (3) The
anti-freezing fortification length determined by the
empirical analysis method has certain feasibility, however, it shall be further
modified according to the temperature data measured in the field. (4) The
calculation model for the frost heaving force on the tunnels in the cold
regions has shortcomings in practical engineering applications, while the
calculation method considering the non-uniform frost
heaving of the freezing circle of the surrounding rock is relatively consistent
with the engineering practice. (5) The anti-freezing
design of tunnels in cold regions shall focus on the proper handling of the
temperature and the groundwater, i.e., the measures for temperature
keeping/increasing and the measures for the anti-freezing
of the drainage system. Furthermore, the limitations of the temperature
keeping/increasing measures and the directions of further researches thereof
are pointed out, and the principles for the arrangement of the anti-freezing measures for drainage systems of tunnels under different
fortification grades are put forward. Additionally, the key points of the
development trends of the anti-freezing technologies
for tunnels in cold regions, such as the distribution pattern of the
temperature field under intricate factors, the mechanism of the freezing-induced damages, the thermal-insulation
materials, and the new thermal-insulation measures, are
proposed to solve the problem of the freezing-induced
damages of tunnels in cold regions.
WU Mengjun
,
FANG Lin
. State of Art and Prospects
of Anti-Freezing Design of Highway Tunnels in Cold Regions[J]. Tunnel Construction, 2025
, 45(1)
: 1
-20
.
DOI: 10.3973/j.issn.2096-4498.2025.01.001
