When the longitudinal
joints with C-T quick connectors are used in
shield water conveyance tunnels, the internal water pressure in the tunnel
decreases the axial force at the joints, which in turn affects the flexural
performance of the joints. However, the axial force effect on the flexural
performance of the joints with C-T quick connectors has
not been adequately investigated. Therefore, a full-scale
compression-bending experiment of C-T quick connector joints under a smaller axial force was carried out
in this study. The experiment results were compared with those of the larger
axial force experiment with the same joint, and the flexural characteristics of
the joint with CT connectors under different axial
forces were summarized. The results show that: (1) Under smaller axial force,
the flexural process of CT connectors joints can be
divided into concrete bending stage and concrete and connectors bending stage.
In the concrete bending stage, the moment firstly increases linearly, and then
the flexural stiffness of the joint decreases continuously. The flexural
stiffness of the joint increases when the C-T
connectors are lapped, after which the connectors yields rapidly and the
flexural stiffness decreases until the joint failure. (2) Under smaller axial
forces, the factors affecting the flexural capacity of the joints are lap,
yield, and fracture of the C-T connectors; the tensile
properties of C-T connectors need to be improved to
prevent premature yielding; while under larger axial forces, the lap and crush
of the outer concrete are the critical nodes in the flexural process of the
joints. Cracks were observed around the connectors under different axial
forces.
WANG Jian, XIONG Bilu, WU Yudong
. Experimental Study on
Flexural Characteristics of Longitudinal Joints with C-T Quick Connectors in Shield Water
Conveyance Tunnel[J]. Tunnel Construction, 2024
, 44(S1)
: 224
-229
.
DOI: 10.3973/j.issn.2096-4498.2024.S1.024
