Differential settlement can easily cause the failure
of the circumferential joint of a shield tunnel. Herein, a case study is
conducted on the circumferential joint of a shield tunnel connected using
diagonal bolts. The failure mechanism of the circumferential joint is revealed
using a fullscale test. Thereafter, the results of the fullscale test are introduced to the circumferential joint of a largediameter shield tunnel connected through bolts using a computational
mechanics method. The results show the failure process of the circumferential
joint of the largediameter shield tunnel connected
using diagonal bolts. Field data demonstrate that the circumferential joint is
the weakness of the shield tunnel. The differential settlement arises along the
longitudinal direction because of the dislocation on the circumferential joint.
Thus, identifying the failure process of the circumferential joint in the
following three stages is essential. (1) Stage 1, the circumferential shear
stress is balanced through friction force, and the shear stiffness of the
circumferential joint is large. (2) Stage 2, the dislocation phenomenon
develops even when the shear stress of the circumferential joint does not increase,
and the shear stiffness reaches zero due to the gaps between a diagonal bolt
and the bolt hole. (3) Stage 3, the shear stress increment of the
circumferential joint is borne by the diagonal bolt, and the shear stiffness of
the circumferential joint varies with the support conditions of the diagonal
bolt and plastic hinge. The analytical solution agrees with the test results.
HE Yuan
,
YANG Zhenhua
,
LIU Xian
,
DING Wenqi
.
Theoretical Solution for Failure Mechanism of
Circumferential Joint of Shield
Tunnel Segment Connected Using Diagonal Bolts
[J]. Tunnel Construction, 2021
, 41(6)
: 933
-945
.
DOI: 10.3973/j.issn.2096-4498.2021.06.005
