城市交通联系隧道不同坡度下限制风速研究

Study on Limited Velocity of Urban Traffic Link Tunnel at the Different Slope Position

针对城市交通联系隧道(UTLT)环形结构的特点,在临界风速的基础上提出限制风速的概念,选取某UTLT主隧道和出入口三处不同坡度的路段,对火场纵向温度场分布规律进行研究,验证了坡度对烟流浮力效应的影响规律,并修正了出入口的排烟原则。根据工程实际,选取隧道坡度作为该UTLT限制风速的影响因素,确定了不同坡度下限制风速的合理范围。

The concept of confinement velocity is based on critical velocity and the characteristics of the urban traffic link tunnel(UTLT)circle structure.Three stretches of road with different grades locating at main entrances and exits of the UTLT were selected in an experiment to study the distribution law of the vertical temperature field at the fire scene and verify the influence law of different grades on plume buoyancy effects,and fix the principles of ventilation at the tunnel entrances and exits.Tunnel slope was selected as the influence factor of the UTLT’s confinement velocity and reasonable range of confinement velocity at different grades was determine according to the engineering practice.