Effects of Belt of Trees on Road Traffic Noise Annoyance

在Tomakomai有和没有树木带的地点以及九州有和没有隔音屏障的地点进行了社区对道路交通噪音反应的调查。Tomakomai和九州分别有268人、92.4%和387人、79.5%的回答率。受访者在人口统计参数方面的分布几乎相同。然而，在有树木带和隔音屏障的地点，一般的烦恼和活动干扰显著减少。特别是在一般烦恼、排气烦恼和开窗困难方面的差异更大。通过通径分析对社会反应和噪声数据进行分析，探讨影响一般烦恼的因素。在有树木带和没有树木带的情况下，排气和振动对一般烦恼的影响都更大。在没有树木的地点，对噪音的敏感性和睡眠质量影响更大，在有树木的地点，道路安全受到的影响更大。在有隔音屏障和没有隔音屏障的情况下，刺激和唤醒的影响都更大。在没有隔音屏障的场所，噪音敏感性和L_<eq>对烦恼的影响更大，在有隔音屏障的场所，电视/广播干扰对睡眠质量的影响更大。由此可见，用树木带和隔音屏障对噪声源进行视觉掩蔽，可以相对提高道路安全性和听音干扰，降低噪声水平和提高视觉效果是重要的噪声措施。

Surveys on community response to road traffic noise were carried out at sites with and without belt of trees in Tomakomai and at sites with and without noise barriers in Kyushu. The total numbers of respondents and response rates are 268,92.4% in Tomakomai, and 387,79.5% in Kyushu, respectively.The distributions of respondents regarding demographic parameters are almost the same. However, the significant reductions of general annoyance and activity interference were shown at sites with belt of trees and noise barriers. Particularly, the differences in general annoyance, annoyance caused by exhaust and difficulty to open windows were larger.Path analysis was applied to the social response and noise data to investigate what factors strongly affect general annoyance. The effects of exhaust and vibration on general annoyance were larger at both sites with and without belt of trees. At sites without trees, sensitivity to noise and quality of sleep affected annoyance more and at sites with trees, safety for road affected more. The effects of irritation and awakening were larger at both sites with and without noise barriers. At sites without noise barriers, sensitivity to noise and L_<eq> affect annoyance more and at sites with barriers TV/radio disturbance quality of sleep strongly affect annoyance.Such results suggest that safety for road and listening interference were relatively increased by visually concealing the noise sources with belt of trees and noise barriers and that not only reducing noise level but also the visual effect are important as noise measures.