traffic noise

bySUNIL GOND

([email protected])

GALGOTIAS COLLEGE OF

ENGG. & TECHNOLOGY

Traffic noise reduction: Future

aspects

What is noise?Noise is excessive, displeasing

human, animal or machine-created environmental sound that disrupts the activity or balance of

human or animal life.

The health effects of traffic noise· Annoyance.· Sleep disturbance.· Disturbed cognitive functioning

(learning and understanding).· Cardiovascular disease.· Adverse effects on mental

health.

noise emmiting sources

traffic

metro

aircra

ft

neigh

bourh

ood

indust

ries

horns

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Characteristics of Vehicle Noise

Exterior road traffic noise Trucks are typically noisiest followed by buses and

motorcycles while cars are the quietest. The contribution of cars to the overall traffic noise

level is great (about 80% of the road traffic). For lower speeds, below 40-50 km/h, engine noise

including exhaust and intake noise dominates for cars. For higher speeds, above 70 km/h, tyre-road noise

dominates the car exterior noise generation. For heavier vehicles the engine noise is dominant

under most conditions. Internal vehicle noise is caused by airborne and

structure borne noise from the engine and tyre-road interaction noise.

vehicle noise and vibration

air pumping and tyre vibration Aerodynamic noise

Noise measurement Brad and Kjaer 2260 Sound Analyser

This device is one of the most widely used for analysis of traffic noise emissions in busy streets and cities.

It measures the noise in A decibels (db A). One db A roughly corresponds to inverse of 40 db (i.e. 1 kHz) ; which equals to the loudness curve of human ears.

Measures for noise abatementEfficient traffic management in cities like New DelhiRestricting use of horns in sensitive spaces like schools, colleges, hospitals

Reducing speed limits

Reducing vehicle speed by 10 km/hr leads to an approximate decrease of 2-3 db of noise from it.

Efficient management of traffic lights

Prohibiting the entry of certain heavy vehicles like trucks in certain part of streets

Proper land use planning and management

Construction measures Tyre width, tyre hardness, groove depth and road

surfaces are pivotal factors affecting tyre noise. an optimal combination of tyre and road surface is

required. ‘Porous asphalt’ has a potential to reduce the vehicle

noise by 5-6 db Poro-elastic pavement when combined with a porous

structure with a soft aggregrate can reduce an unbelievable noise of 10-12 db for normal tyres and 13-15 db for studded tyres

STC (Sound Transmission Class) – it is an integer rating of how well a building partition attenuates an air-borne sound. The better the STC of a material, the better sound insulation it provides.

Governmental measures Strict rules and regulations have to be devised for

vehicle-spare-part producing companies (for manufacturing of engines, tyres, etc.) to follow the CPCB noise limits or else their certification would not be easy.

THE NOISE POLLUTION (REGULATION AND CONTROL) RULES, 2000

Luxury Limousine 77dB Small passenger car 79dB Miniature passenger car 84dB Sports car 91dB Motor-cycle (2 cylinder 4 stroke) 94dB Motor scooter (1-cylinder-2-stroke) 80 dB

Environmental MeasuresPlantation of trees, shrubs and hedges

alongside the road and highway or on the road partitions.

Mitigation - Barriers

THE TWO

MODELS

THE TOPSIS MODELIt is based on the concept that

the chosen approach should have the shortest distance from the Positive Ideal Solution (PIS) and have the farthest distance from the Negative Ideal Solution (NIS). A fuzzy combination of TOPSIS with some linguistic variables pave the way to make an appropriate decision.

THE RTM(Road Traffic Model)for carrying out the generation of the

noise levels along the Indian roadRoad traffic noise model rely on the

◦ volume of vehicles ◦ percentage of heavy vehicle◦ the mean speed of vehicles ◦ the several road conditions such as height

and width of road as well as road gradient.

For a better tomorrow…The Administration and citizens must co-

ordinate with each otheroptimum CPCB (Central Pollution Control

Board) limit of 60 db.Sustainable developmentby observing the present traffic conditions.This data could be used variety of

organizations for generating the noise levels reports for serving variety of purposes.

THANK YOU!!

YOUR Questions please…

traffic noise

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