To clean the obstacles encountered during a shield
tunnel crossing underneath operational station in waterrich
sandy stratum, a case study is conducted on Wuhan metro line 12 crossing
underneath an operational station, and a construction scheme, opencut obstacle cleaning shaft, obstacle cleaning by longitudinal
freezing in shaft, and shield tunneling after backfilling with plain concrete,
is proposed. First, the allowable deformation control indicators for the
existing operating station are given by referring to industry standards and
similar cases. Second, mechanical analysis is conducted on freezing excavation,
obstacle cleaning shaft excavation, and shield tunneling using finite element
numerical method, and key technical points of design and construction of each
process are proposed. Finally, according to analytical results of the measured
deformation data on site, the deformation of the existing station floor is within
the range of the calculated value by finite element. The proposed scheme
ensures the controllable deformation of the existing operational station,
addresses water inrush and collapse problems during manual breaking of the
underground obstacles in waterrich sandy layer, and
improves the safety of the new tunnel passing through the underground
structural obstacles.
ZHU Min, XU Chen, WANG Zihao
.
Mechanical Analysis and Engineering Application of Obstacles Clearing Using Freezing Method Under
Existing Operational
Stations in WaterRich Sandy Layer
[J]. Tunnel Construction, 2023
, 43(S2)
: 395
-405
.
DOI: 10.3973/j.issn.2096-4498.2023.S2.044
