The main strata in Qiandao Lake water distribution
project are sandstone and quartz sandstone with high quartz content, shallow
overburden and multiple faults, among which grade Ⅳ surrounding rock accounted for 52%. The construction period of the project is
tight, and the demand for tunnel boring machine(TBM) advance rate is high.
Based on such special geological conditions, the TBM selection and targeted
design are conducted for Qiandao Lake water distribution project. The doubleshield TBM is adopted, the cutterhead is designed with highstrength box structure, the disc cutters are arranged in nonlinear
way, and the cutter spacing and muck outlet are optimized. By controlling the
exposed length of cutterhead, enhancing the ability of cutterhead to expand,
adopting main drive lifting design, large torque and large thrust design, the
grade Ⅳ broken surrounding rock and fault can be
driven. The smallhole diameter TBM logistics and
transportation platform is optimized. The engineering practice results show
that the TBM cutterhead design has high reliability and can guarantee efficient
rockbreaking performance. The overall perfectness
ratio is up to 97% and the machine advanced 3151.58 m in 92 days. Additionally,
the TBM has successfully advanced through grade Ⅳ fractured rock and faults effectively and quickly with all systems running in
favorable conditions.
ZHANG Xinwei
.
TBM Selection and Key Technologies of Qiandao Lake Water Distribution Project
[J]. Tunnel Construction, 2021
, 41(S2)
: 612
-619
.
DOI: 10.3973/j.issn.2096-4498.2021.S2.078