Research On Traffic Noise Spectrum Of Tianjin Typical Road System And Sound Insulation Performance Of Exterior Window

With the rapid development of China's economy,the problem of environmental pollution is becoming more and more serious.Especially the noise pollution of urban traffic has become the primary problem of all major cities in China.Under the proposal of “Integration of Beijing,Tianjin and Hebei Strategy”,as China's third municipalities,Tianjin is identified as the national advanced manufacturing base,core area of north international shipping transportation,financial innovation demonstration zone and the advanced reform and opening up area.The city's traffic pressure is increasing;meanwhile the traffic noise pollution is especially serious.This paper not only analysis of traffic noise pollution in city,but also gives the sound insulation performance of the typical building exterior window in Tianjin through the research of the representative road traffic noise spectrum in Tianjin,and draws the following conclusions:1.No matter when it comes to the urban expressway,urban trunk roads,urban roads,or city branch,the relationship between traffic flow and the sound pressure level is stable.When the traffic flow becomes larger,the sound pressure level becomes larger as well.The overall performance among each road level and the size of sound pressure is primary roads > expressways> trunk roads > branch roads.2.The spectrum distribution of different road traffic noise has similar characteristics.The level of sound pressure in the low frequency part of 125 Hz is higher,while the middle frequency of 125Hz-1600 Hz is normally flat.In the high frequency part of 1600 Hz,the sound pressure level decreases with the increase of the frequency band.3.If only considering the premise of sound insulation performance,the pros and cons of typical building exterior window performance is: steel single-layer glass(double-layers window)> new type aluminum flat-open hollow glass window > aluminum flat-open glass chamber window > steel single-layer glass window > original aluminum flat-open hollow glass window > aluminum alloy single layer glass window > normal plastic steel hollow glass window4.The sound insulation of the seven types of window is increased with the increase of the frequency.Furthermore,the sound insulation of exterior windows is the opposite of the road traffic noise spectrum curve because the traffic noise is mainly distributed in the middle and low frequency.5.For those existing buildings which already installed one of those seven kinds of window yet still not up to the standard of indoor noise,people need to carry on the reformation of the existing window.