Noise barriers are to mitigate highway noise pollution:
High level noise is a disturbance to the human environment. Because of urbanization, noise in all areas in a city has increased considerably. One of the most pervasive sources of noise in our environment today is those associated with transportation. People reside adjacent to highways, are subjected to high level of noise produced by trucks and vehicles pass on the highways. Prolonged exposure to high level of noise is very much harmful to the health of mankind.
Artificial noise barriers are solid obstructions built between the highway and the residential areas along a highway. They block major portion of noise produced by passing vehicles on a highway. Effective noise barriers typically reduce noise levels by as much as half or more. The construction of noise barrier may be built in the form of earth mounds, vertical wall along the highways for creation of blockage of sound generated by heavy vehicles. The effectiveness of mitigation of sound depends upon the height of the mounds or walls. Function of noise barriers are: (1) it can reduce the loudness of traffic noise by as much as half; (2) It may not completely block all traffic noise, but gives certain relief to the residents; (3) It may be effective, regardless of the material used; (4) It must be tall and long with no openings for making it more effective; (5) It must be designed to be visually appealing looking into the aesthetic value of the site.Apart from constructing artificial noise barriers, creation of greenbelt, by plantation of trees along the highways. The space between the residences and highways may be utilized for creation of greenbelt. As more and more noise pollution problem is being cropped-up, city planners are increasingly adopting various methods to