Existing standards for gas hazards in traffic tunnels
have several limitations, including overly stringent safety measures and high
construction costs that are not feasible in high-altitude
regions. To address these issues, numerical simulation and theoretical analysis
methods are employed in this study. A numerical model is developed to analyze
the dynamic spatial variations of average wind speed and gas concentration,
leading to the proposal of safety factors for both wind speed and gas
concentration and the determination of the stable return airflow section. The
study simulates high-altitude environmental conditions
to reveal the mechanisms by which altitude influences gas explosion
characteristics, explosion limits, and gas concentration. Altitude-based coefficients for gas explosion limits and concentration are
introduced to establish a correlation model to link gas tunnels in flat regions
with those in high-altitude regions. The main findings
of the study are as follows: (1) A revised calculation formula for the
classification standards of gas work areas in traffic tunnels is proposed,
incorporating adjustments for the cross-sectional area
of return airflow sections. (2) The disequilibrium coefficient for gas emission
is optimized and integrated into the calculation formula for measured absolute
gas emissions during the construction phase, along with safety factors for wind
speed and gas concentration, to yield a modified formula. (3) For high-altitude gas tunnels, a classification standard suitable for varying
altitudes is proposed, including a formula for calculating classification
values and standards.
LIN Zhi
,
JIANG Xingyao
,
CHEN Xiang
,
DING Yongchao
,
FENG Sen
. Classification Standards for Gas Work Areas in Traffic Tunnels and Influence of Altitude[J]. Tunnel Construction, 2025
, 45(5)
: 876
-886
.
DOI: 10.3973/j.issn.2096-4498.2025.05.002
