The rectangular pipe jacking tunnel under Nanhu avenue
in Jiaxing, China, is the world′s first 15m
diameter and threelane pipe jacking tunnel. Targeted
designs are implemented on the multicutterhead
excavation, antifriction slurry grouting, and triple screw conveyor mucking
systems to ensure the safe and efficient excavation of superlarge crosssection pipe jacking under
shallow soil and small clear distance conditions. Furthermore, statistical
analysis is conducted on the main tunneling parameters of the pipe jacking
machine and ground settlement monitoring results. Some conclusions are drawn as
follows: (1) The friction reduction measures adopted effectively reduce the
ground friction resistance of the pipe joint, and the actual total thrust is
approximately 40% of the theoretical value. (2) The cutterhead diameter and
mounting height considerably affect the torque. The average torque is less than
half of the rated torque, so it can be optimized. (3) In the pipe jacking
process, the shield shell is subjected to large stratum extrusion pressure, the
residual earth pressure in the soil chamber is significantly greater than the
lateral earth pressure of the stratum, and they both reduce after shield
shutdown. (4) After pipe jacking excavation, the transverse surface settlement
groove shows a U shape, and the stratum settlement within 0.5 times the
excavation width on both sides of the tunnel is large.
WANG Famin
,
MENG Qingjun
,
ZHANG Hao
,
LIU Changli
,
YANG Zhenxing
,
ZHANG Bing
. Analysis of Tunneling Parameters of a ShallowBuried
SuperLarge CrossSectional Rectangular Pipe Jacking Tunnel[J]. Tunnel Construction, 2023
, 43(2)
: 316
-326
.
DOI: 10.3973/j.issn.2096-4498.2023.02.013
