The monitoring programme was undertaken simultaneously in
an urban background site and in the longest road tunnel of the
municipality (Fig. S1). It serves as a gateway to the city,
connecting the Central and António Macedo avenues to the
Liberdade Avenue. It was completed in 2009 and is known as
Liberdade Avenue tunnel. After the construction of this road
infrastructure, Liberdade became the major pedestrian avenue
of Braga's historical downtown. The tunnel consists of a single
parallepipedic shaped reinforced concrete bore that is 1040 m
long, carrying two lanes in most of its extension of one-way
traffic. The tunnel possesses smoke extraction fans, which are
automatically connected when CO reaches critical levels, but
the ventilation system was cut off during the sampling
campaign. The instruments were installed on the left sidewalk
at approximately 450 m from the exit. Traffic volume by vehicle
type through the tunnel was counted manually at 15-minute
intervals throughout each of the sampling days (8:00–20:00 h,
local time).
The monitoring programme was undertaken simultaneously inan urban background site and in the longest road tunnel of themunicipality (Fig. S1). It serves as a gateway to the city,connecting the Central and António Macedo avenues to theLiberdade Avenue. It was completed in 2009 and is known asLiberdade Avenue tunnel. After the construction of this roadinfrastructure, Liberdade became the major pedestrian avenueof Braga's historical downtown. The tunnel consists of a singleparallepipedic shaped reinforced concrete bore that is 1040 mlong, carrying two lanes in most of its extension of one-waytraffic. The tunnel possesses smoke extraction fans, which areautomatically connected when CO reaches critical levels, butthe ventilation system was cut off during the samplingcampaign. The instruments were installed on the left sidewalkat approximately 450 m from the exit. Traffic volume by vehicletype through the tunnel was counted manually at 15-minuteintervals throughout each of the sampling days (8:00–20:00 h,local time).
การแปล กรุณารอสักครู่..