To improve the bearing capacity, reliability, and
safety of main bearing seal of largediameter shield (over 9 m),
the structure, working principle, and properties of two main bearing seals are
investigated, and case analyses are conducted. Then, finite element analysis is
employed to study the contact stress of the seals, and the pressure and
tunneling data of the two main bearing seals in dozens of largediameter shields are comparatively analyzed. The results reveal the
following: (1) The bearing capacity of labiates seal structure with wedge
protruding is higher than that without wedge protruding, which can bear
excavation chamber pressure of no larger than 0.6 MPa without compensatory
pressure. (2) Under the condition of excavation chamber pressure of larger than
0.6 MPa or momentary large fluctuation of excavation chamber pressure, the
labiates seal structure is potentially brokendown due to delay operation or
response of pressure compensation system. (3) The maximum positive dynamic
bearing capacity of singlechannel fingertype seal is 1 MPa, thus the fingertype
seal is recommended when the excavation chamber pressure ranges from 0.4 MPa to
1 MPa without arrangement of a pressure compensation system, which still can
improve the bearing and pressurizing capacity of main bearing seal structure.
LI Taomeng, SUN Haibo, CHEN Qiankun, WANG Xin
. Comparative Analysis of Properties between Two Main
Bearing Seals of LargeDiameter
Shield Tunneling under High Water Pressure[J]. Tunnel Construction, 2022
, 42(S1)
: 517
-525
.
DOI: 10.3973/j.issn.2096-4498.2022.S1.061
