The authors establish a
theoretical model for the mechanical response of advance long-pipe roofs, considering the influence of pipe roof overlap and
support conditions at both ends. Using the finite difference principle, a
calculation method for deflection at various pipe roof positions is developed.
The model examines the influence of pipe roof diameter, excavation spacing, and
pipe roof overlap on deflection changes. Furthermore, a case study on the
Haicang tunnel in the Xiamen Second West Passage is conducted to optimize its
reasonable excavation spacing. The results indicate the following: (1) The
maximum error of the proposed model is only 8.14% compared to the field test
results, and pipe roof overlap eliminates the unreasonable upward arching of
deflection. (2) Increasing the pipe roof diameter gradually decreases the
maximum deflection, but the reduction effect weakens. (3) At an excavation
spacing of 1.2 m in the Haicang tunnel, the crown deflection is reduced by
67.35% compared to that without a pipe roof, and the maximum principal stress
of the primary support is adjusted to a more uniform state.
CUI Lingyue
. Mechanical Response
Characteristics and Engineering Applications of Advance Long-Pipe Roofs for Tunnels[J]. Tunnel Construction, 2025
, 45(1)
: 120
-131
.
DOI: 10.3973/j.issn.2096-4498.2025.01.009
