摘要
为研究隧道施工通风过程中风筒破损对一氧化碳(CO)排出的影响,依托城开高速鸡鸣隧道,运用孔口流量理论,考虑风筒内流速、孔口与开挖工作面距离和孔口数量3个因素,基于数值模拟方法,研究风筒破损对CO排出的影响。结果表明:在风筒破损面积相同的前提下,漏风率随送风量的增加而增大;开挖工作面处的CO浓度在通风1 min后达到峰值,约为3.5%;风筒破损会对隧道内的CO稀释产生滞后效应,滞后时间为1~3 min并且送风量越小滞后效应越明显,最终导致达到预计通风时间后距洞口约15 m范围内的CO浓度仍高于规范要求;通风长度区域内,3个因素中对CO排出的影响依次为:风筒内流速>孔口与开挖工作面距离>孔口数量;整体隧道内,影响依次为:风筒内流速>孔口与开挖工作面距离>孔口数量。并提出了通风设计和孔洞修补两方面的建议。
To investigate the influence of damaged duct on carbon monoxide’s emission during tunnel construction, relying on the Jiming Tunnel of Cheng-kai Expressway. The orifice flow theory was used to analyze, and the velocity in duct, the distance between holes and working face and the number of holes were considered as factors. The orthogonal test was carried out to research the influence of duct damage on the distribution of CO. The results show the air leakage rate increases by the increase of the air of the working face. When the ventilation time is 1 min, the CO concentration reaches its peak at the working face, which is about 3.5%. A lag effect on the dilution of CO in the tunnel causes by the damage of duct. And the lag time is 1 to 3 minutes, and it is more obvious with the decreasing of air demand at working face. Finally, after the expected ventilation time is reached, the CO concentration within about 15 m from the hole is still higher than the specification requirements. In ventilation region, the influence degree of the three factors on the dilution and discharge of CO is as follows: the velocity in the duct > the distance between the holes and working face > the number of holes. In the whole tunnel, the influence order is: the velocity in the duct > the distance between the holes and working face> the number of holes. There are suggestions on ventilation design and holes repair.
作者
王林峰
冉楗
钟宜宏
李玲玉
李鸣
WANG Lin-feng;RAN Jian;ZHONG Yi-hong;LI Ling-yu;LI Ming(Key Laboratory of Geological Hazards Mitigation for Mountainous Highway and Watery,Chongqing Municipal Education Commission,Chongqing Jiaotong University,Chongqing 400074,China;Road&Bridge International Co.Ltd.,Beijing 101121,China)
出处
《科学技术与工程》
北大核心
2022年第24期10718-10725,共8页
Science Technology and Engineering
基金
重庆市自然科学基金(cstc2020jcyj-msxmX0218)。
关键词
隧道工程
一氧化碳浓度
风筒破损
送风量
正交试验
极差分析
tunnel engineering
carbon monoxide concentration
damaged ventiduct
air volume
orthogonal test
range analysis
