The failure mechanism of double-arch
tunnels due to voids behind lining and the relevant maintenance technology
remains scarce. As a result, a similar model test and finite element simulation
are performed to investigate earth pressure distribution, structural safety,
and failure laws as the location and size of a void behind lining change. The
results show that: (1) Due to a void behind the lining, the earth pressure
acting at the spandrel inside is larger than outside, and the largest value
occurred at the en echelon area. (2) A change in the void location causes
significant differences in the distribution pattern and propagation law of
cracks at the crown and haunch of the tunnel on the same side of a void;
however, it has little effect on the bottom of the double-arch tunnel. (3) When there is a void behind the central wall, the
crown's minimum safety factor appears, and the crack with the greatest area
appears earlier than in the other cases. (4) As the size of the void at the
crown increases, the lining at the arch connected with the central wall is
prone to cracking, resulting in serious failure. The angle of the void has a
greater influence on lining failure than the height of the void. These cracks
appear earlier as the void angle increases, on both sides of the void and at
the left arch feet. The findings revealed the distribution law and process of
crack propagation in double-arch tunnels caused by
changes in the location and size of voids behind the lining. The large voids
detected behind the linging of double-arch tunnels
should be grouted timely.
ZHANG Xu
,
HUANG Shimin
,
XU Youjun
,
MAN Zhongang
. Impact of Voids Behind Lining on Stress and Failure
of Double-Arch Tunnels[J]. Tunnel Construction, 2022
, 42(1)
: 90
-102
.
DOI: 10.3973/j.issn.2096-4498.2022.01.012
