MEASURMENT OF HIGHWAY TRAFFIC NOISE AND DESIGN OF ACOUSTIC BARRIER FOR ITS CONTROL

Abstract

In the present work an attempt has been made to study the noise level at highway, NH-58 and designing the acoustic barrier for the control of high way traffic noise. The site chosen was a part of highway where residences of IIT faculty members are there. A series of noise levels were measured at different selected points around the highway at different time intervals on number of days and both sides of highway to assess the traffic noise.. The parameters considered were traffic volume, percentage of heavy trucks and buses and equivalent distance, speeds. The data collected were, percentile noise levels,L10 equivalent. noise level,Leq,traffic parameters like speeds, types of vehicles and their number passing through. Noise impact is assessed according to above data collected. Then attenuation required is assessed. It has been found that the existing noise level is much above the desired level Leq of 67 dB (A). Hence height of barrier along the road side has been evaluated in this work as an attempt to circumvent the annoyance caused to residents on the basis acoustics observations. Height of barrier, position of barriers from source and receiver, barrier break and line of sight were evaluated with the help of barrier nomograph.A general design procedure for evaluating the acoustic height of the barrier to be used for control of traffic noise in a highway has been discussed in the present work.