The total length of the tunnel created during the
water supply project in northern Xinjiang is 514 km, consisting of 18 open
tunnel boring machine (TBM) clusters. Work on this scale is rare, both in China
and abroad. To understand the boring law, the authors make a statistical
analysis of the equipment parameters and related indexes, machine jamming, and
the support of cluster tunneling over the past 2 years. The average monthly
footage of the 18 machines used in the project was 385.2 m, the highest monthly
footage was 1 136 m, the average utilization rate was 28%, 〖JP+2〗the average intact rate was 91%, the average failure rate was 9%,
and the number of cutter changes per extension meter was 0.02~0.45, indicating
that the equipment has good adaptability. However, there were also some
problems, such as abnormal cutter wear, high belt and anchor drill failure
rate. In the process of longdistance TBM cluster
tunneling, targeted treatment measures should be taken according to different
jam types and different water gushing conditions. The tunnel support form and
support parameter design should be adapted to the construction characteristics
of the equipment, and the equipment should also be improved during
manufacturing according to problems that arise, such as bolting nonvertical rock surface. In general, the efficiency of TBM cluster
tunneling is high, but there are still some issues, and it remains necessary to
make continuous efforts to achieve the longterm safe
and efficient tunneling.
DENG Mingjiang
,
TAN Zhongsheng
.
Study on Boring Indexes and Key Issues of Tunnel Boring
Machine Cluster Construction of Super-Long Tunnels
[J]. Tunnel Construction, 2021
, 41(11)
: 1809
-1826
.
DOI: 10.3973/j.issn.2096-4498.2021.11.001