UTE Line 9
Description of the Environmental Measure
Problem detected:
In the tunnel for Line 9 of the Barcelona Underground, noise levels from the conveyor belt carrying excavated material , the rubble tip, the cranes and the conveyor line were higher than allowed by legislation and were potentially a signifi cant nuisance to nearby residents as work was being done around the clock.
Solutions adopted:
Because the construction site was in an urban area, and considering the amount of noise being emitted, it was decided to erect a 60x10-metre metal structure with soundproof panels to reduce the acoustic impact of the conveyor belt and auxiliary machinery. A 4,000-m2 soundproof roof was also built over the TBM crossing shaft in the La Sagrera zone.
Results:
Installing acoustic panels brought the noise levels down considerably (by about 30 dB), as shown by the acoustic studies conducted periodically during execution.
