顶部开口的城市浅埋公路隧道内气压脉动特性及分布规律

Pressure wave pulsation behavior and distribution pattern of shallowly buried urban road tunnels with top openings

顶部开口的城市浅埋公路隧道是一项绿色节能技术,南京已经建成4条此类隧道。自运营以来,隧道内空气环境质量得到了广泛好评,但是尚未形成规律性的设计方法。基于1∶10的实验平台,测试了4种工况下隧道内部的气压脉动及分布。结果表明:在均匀连续的车流下,隧道内各点的逐时压力表现为周期不对称的类正弦脉动。气压脉动的振幅随高度增加而降低。在均匀连续车流下的某一个固定时刻,公路隧道内沿长度方向的压力也呈现周期性的脉动分布。在顶部开口附近,周期性的气压脉动依然存在,但振幅出现衰减。

Shallowly buried urban tunnels with top opening are a type of green technique that saves energy.Four such tunnels have been built in Nanjing.The in-tunnel air quality has obtained extensive appraises since their being put into operation,but no regular design procedures has ever been developed. Based on a 1：10 scale experimental platform,pressure pulsation and distribution in the tunnel were tested for 4 different working conditions. Results suggested that with a steady and continuous traffic flow,the time-wise pressure at each point in the tunnel was characterized by periodical and asymmetrical sinusoid-like pulsation.The amplitude of pressure pulsation decreased with increasing height.Atagiven moment with a steady and continuous traffic flow,the lengthwise pressure in the tunnel also displayed a periodical pulsation distribution pattern. It still existed periodical pressure pulsation with an attenuated amplitude in the vicinity of the top opening.