Adaptive design of dualmode
shield in waterrich gravelmudstone
composited strata is of great significance. As a result, the targeted designs
of structure and functional system of slurry/earth pressure dualmode shield used in Wuyi Interchange stationXinxiu Park station on Nanning Rail Transit Line No. 5 are put
forward according to the construction risks such as crossing through Yongjiang
River, crossing underneath buildings with shollow foundations, surface
settlement induced by shield boring in gravelmudstone
composited strata, and muck cake on cutterhead. As for structural design, the
air cushion chamber is used to stabilize slurry pressure, and the slurry
discharge port is optimized so as to realize the stable control of surface
settlement. The brush and P0 pump circulation systems are set on central panel
and bracket to effectively reduce the mud cake phenomenon. The design of screw
conveyor is optimized to reduce the gushing pressure, and compared with the
adjacent lines, the boring speed of the rivercrossing
section is increased by nearly one time. As for functional system, mucking
system conversion between slurry and earth pressure dualmode is realized, the total thrust of the propulsion system reaches
39 910 kN, which can meet relevant requirements under different working
conditions, the surface settlement is strictly controlled according to grouting
system and rational tunneling parameters control.
HUANG Zhonghui
,
CHEN Fan
,
MENG Qingjun
,
LIU Chuankun
,
CHENG Fan
,
WANG Shimin
,
YAO Chaofan
. Analysis of Risks and Targeted Design of Dualmode
Shield in Composited Strata[J]. Tunnel Construction, 2020
, 40(S2)
: 297
-305
.
DOI: 10.3973/j.issn.2096-4498.2020.S2.038
