To mitigate the impact of large-scale
blasting construction on adjacent sensitive structures and to further enhance
controlled blasting techniques under constrained conditions, a case study is
conducted on the construction project of the No. 2 shield launching shaft of
the Guifengshan tunnel on the newly built Zhuzhou-Zhaoqing
high-speed railway. Based on the safety requirements of
deep shaft blasting adjacent to high-voltage
transmission towers and a 500 kV substation, a detailed vertical-layered and horizontally-zoned blasting
scheme is developed. The scheme integrates pre-split
blasting, main charge hole blasting, and contour blasting, along with vibration
attenuation and control measures. The feasibility of the blasting plan and
vibration control methods is verified through empirical formulas and experimental
testing, including safety checks of key blasting parameters and test blasting
analyses. Monitoring during construction confirms the effectiveness of the
blasting control. The findings indicate that: (1) The proposed blasting design
and control techniques are well-suited for deep shaft
excavation under complex site constraints. (2) Both empirical vibration
formulas and field tests demonstrate that the combined blasting and vibration
mitigation approach is feasible, with vibration velocities at the transmission
tower and within the substation remaining below the safety thresholds of 2 cm/s
and 0.6 cm/s, respectively. (3) Field monitoring also confirms that shaft and
structural settlements stay within allowable limits, and vibration near the
ultra-high voltage substation does not exceed critical
thresholds.
TAN Jianbing
,
YANG Jianli
,
CAO Weiming
,
SHI Chenghua
,
PENG Xingyu
.
Blasting Excavation Control Technology for Ultra-Deep
Shafts Adjacent to Extra-High Voltage Substations
[J]. Tunnel Construction, 2025
, 45(S1)
: 308
-317
.
DOI: 10.3973/j.issn.2096-4498.2025.S1.030
