Survey and measurement of the vehicle pollutant emission in urban underground bifurcate tunnel, China

Abstract More and more bifurcation tunnel structure forms are used in the construction of urban underground tunnel projects. Tunnel traffic characteristics change with the change of the tunnel structure, and the pollutant emission and diffusion will also change in the tunnel. In order to grasp the traffic characteristics, the dynamic vehicles emission and the distribution characteristics of traffic velocity and pollutants concentration, the research team conducted a survey on four typical urban tunnels in China during 2011–2015 through status survey and field measurement. The survey includes traffic characteristics (traffic flow, average speed), vehicle emission characteristics, CO and NOx concentration distribution characteristics in the tunnel. The result can provide a quantitative assessment method to support pollutant concentration ventilation control and energy saving operation in urban bifurcate tunnel.