摘要
针对隧道群中毗邻隧道间的相互影响进行模型实验及数值模拟研究。模型实验基于相似化、自模化理论通过对模型隧道内壁面加糙的方法,建立了几何比尺为1∶40的公路隧道模型,模拟值与实验值基本吻合,最大相差仅8%,验证了模拟值的可信性。并提出了减少毗邻隧道污风混入率的小范围错开理论,结果显示:对于相距13 m、50 m的毗邻隧道,上下游仅错开4 m,污风混入率便可由96.23%,80.44%减少到61.64%,44.64%,这对于减少上下游隧道间的通风窜流是十分有效的。数值模拟结果显示:当隧道距离大于400 m,上游隧道射流风速小于2 m/s时,毗邻隧道二次污染百分比小于5%。因此提出以400 m作为隧道群中毗邻隧道和连续隧道的划分依据。微风天气下(3.4 m/s),上下游隧道间距大于30 m,可以不考虑上游隧道出口污染空气对下游隧道的影响。
This paper studies the interaction effect of adjacent tunnels in tunnel group by means of model tests in combination with numerical simulation. Based on the theory of similarity and auto simulation,with increasing the wall roughness of tunnel model,in the experiment a highway-tunnel model is set up with geometric scale of 1 ∶ 40. The analog value is consistent well with experimental values and the maximum difference is only 8%,the conclusion verified the credibility of simulation value. The theory of small scale separation for reducing the secondary pollution percentage shows that according to the adjacent tunnel with the distance of 13 m and 50 m,the secondary pollution percentage will reduce from 96. 23%,80. 44% to 61. 64%,44. 64% by staggering 4 m. The result of numerical simulation shows that the secondary pollution of adjacent tunnel will decrease to 5% on the condition of the distance longer than 400 m and wind speed less than 2 m / s. Therefore,we suggest 400 m as the classification standard of adjacent tunnel or continuous tunnel in tunnel group. When the wind speed between the tunnels is 3.4 m / s and the distance longer than 30 m,the interaction effect needn＇t to be considered.
出处
《地下空间与工程学报》
CSCD
北大核心
2015年第3期781-787,共7页
Chinese Journal of Underground Space and Engineering
基金
山西省交通建设科技项目(11-2-13)
沪江基金资助(D14003)
国家自然科学基金(51208298)
上海市教委科研创新项目(13YZ070)
上海市教委重点学科建设项目(J50502)
关键词
毗邻隧道
污染物
二次污染
模型实验
数值模拟
自模化
adjacent tunnel
pollutant
secondary pollution
model experiment
numerical simulation
auto simulation
