When superlarge diameter slurry shield tunneling in a
subsea tunnel with a highstrength granite bedrock protruding
stratum (saturated uniaxial compressive strength of 41.7~214.0 MPa), problems
such as uncertain rock breaking effect, difficult driving parameters selection,
abnormal damage of cutters, frequent tool replacement, and high construction
risk are always encountered. Therefore, a laboratory test is conducted on
shield rock breaking to analyze the advantages and disadvantages of blasting
pretreatment and direct excavation. The 100 mm cutter spacing is then verified,
and the control index of penetration degree is proposed under the premise of
ensuring no overload. Furthermore, a shield tunneling parameter control
principle of "penetration control as main, speed control as assistance,
and strict cutterhead torque fluctuation control" is summarized based on
the field tunneling tests, and the cutterhead rotation speed of 1.0 r/min and
penetration degree of 3 mm/r when superlarge diameter
shield directly tunneling through bedrock protrusion section is determined. The
superlarge diameter shield successfully passed through
the highstrength bedrock protruding stratum after
cutting tool monitoring and management.
WANG Guo′an
,
WANG Chaofeng
,
CHEN Qiao
,
ZHANG Wenxin
.
SuperLarge Diameter Shield Tunneling
Method in Extremely Soft and Hard Composite
Strata: a Case Study of Shantou Bay Tunnel
[J]. Tunnel Construction, 2022
, 42(5)
: 892
-899
.
DOI: 10.3973/j.issn.2096-4498.2022.05.016
