浙江杭绍台高速公路特长隧道通风与排烟系统设计与实践

通风系统是维系公路特长隧道正常服务的重要机电设施,通常设备规模和安装功率庞大,但实际建成通车后却出现较高的闲置率。为了降低通风系统规模、运营能耗和闲置率,合理的通风模式至关重要。以浙江杭绍台高速公路三座长度超过5 km的特长隧道通风系统设计为例,介绍了通风系统设计的理念。其中陈家山隧道和镜岭隧道采用了互补式通风方案,并设置小断面竖井以满足排烟长度的要求;大盘山隧道采用传统双竖井送排式通风模式,对比分析了两种不同的通风设备的设置策略,推荐首先设定隧道内的设计风速不大于交通活塞风速,进一步确定竖井尺寸和通风设备规模。上述设计理念有效降低了杭绍台高速公路特长隧道通风系统设施的安装功率,为减少今后运营期间的设备闲置打下基础。

Design Practice of Ventilation and Smoke Exhaust System for Super Long Tunnel of Hangzhou-Shaoxing-Taizhou Expressway in Zhejiang Province

As a vital electrical facility,the ventilation system contributes to the normal service of any expressway super-long tunnel. The ventilation equipment scale and installation power are usually huge,however,there is a high idle rate happening in service period. To reduce the scale of ventilation system,operation energy consumption and idle rate,reasonable ventilation mode is the key problem. Taking the state-of-art ventilation system design of three super-long tunnels longer than 5 km on Hangzhou-Shaoxing-Taizhou Expressway in Zhejiang Province as an example,this paper introduces the design concept of the ventilation system. Chenjiashan tunnel and Jingling tunnel adopt the complementary ventilation scheme,and a small-section shaft is set to meet the requirements of maximum smoke exhaust length. Dapanshan tunnel adopts the double shaft ventilation mode.Two setting strategies of ventilation system are studied and compared. Then it is suggested that tune the design air flow speed in the tunnel close to the traffic piston wind speed,further determining the shaft size and ventilation equipment scale. This strategy effectively reduces installation power of the ventilation system in road tunnels,and lays a firm foundation to mitigate equipment idleness in the future operation period.