|其他題名: ||A study on indoor noise in the train compartment in a railway system|
|作者: ||簡欣愷;Chien, Shin-Kai|
|關鍵詞: ||室內噪音;軌道系統;Indoor Noises;Railway System|
|上傳時間: ||2011-12-28 19:25:32 (UTC+8)|
Along with social progress, the rapid growth of economy and industry, and the increase of urban population due to urbanization, public transportation has grown rapidly to come up with the rate of population increase. Although the growth of public transportations has brought convenience for the public, the impact of traffic noise on passengers has also increased. In the future, it is advised to get prepared for the higher demand for quality of life from the public by attenuating noise at railway systems to reduce its impact on the speech articulation of passengers so as to create a comfortable riding environment for the public.
1. To investigate and analyze the indoor environment at such rail systems as Taiwan Railway, Taiwan High Speed Rail, Taipei MRT and Kaohsiung MRT, including platforms, station halls, access lanes and train compartments.
2. To establish recommended values for indoor noise quality at domestic rail systems.
3. To formulate and provide improvement plans and methods for rail system operators to use as reference in their improvement projects.
Recommendations based on measurement results:
1. The measurement results show that the primary noise source at station halls is from human voice. Stations with bigger passenger volume have higher measured values, while those with smaller passenger volume have lower measured values. The reverberation time measured was 2.3 and 2.4 seconds, which are within the acceptable range in terms of speech articulation. Addition of some kind of sound-absorbing materials would be helpful to increase speech articulation.
2. The measurement results show that the primary noise source at platforms is from train approaching and leaving. Passenger volume is not significantly related to the noise level at the platform. While platform screen doors function to effectively isolate the noise caused by train approaching and leaving, half platform screen doors create more reflection surfaces, which tend to make the platform even noisier than platforms without platform screen doors.
3. The measurement results show that the primary noise source in train compartments is from train vibration. The noise levels differ under different topographic positions. For example, when the train is running on an underground section, the noise produced by train vibration hits the tunnel walls and reflects back to the train to make the internal compartment even noisier. Therefore, the noise level measured in the underground section is slightly higher than that measured on the ground section and overpass section. The train compartment is more crowded during peak hours than during off-peak hours. The noise level measured during off-peak hours is higher than that measured during peak hours. It is probably because that during peak hours, more people are in the compartment, who make more reflection and absorption surfaces, hence reflect and absorb more noise caused by train vibration, while during off-peak hours, less people are in the compartment, who make less reflection and absorption surfaces, hence reflect and absorb less noise.