隔声窗隔声性能的现场监测方法及效果初探

采用隔声窗作为典型道路的交通噪声控制措施，探索隔声性能的现场监测方法。分别选取真空玻璃窗与中空玻璃窗进行监测，两种隔声窗对交通噪声1000 Hz 和2000 Hz 两个倍频带的隔声量最大，真空玻璃隔声窗对500 Hz 倍频带及以下的噪声比中空玻璃隔声窗更有效，如果采用两种隔声窗进行组合，在全频带的隔声量达到25 dB。     

城市典型高架复合道路交通噪声污染模拟及防治对策

与一般城市道路相比,城市高架复合道路通行能力大、行车速度高、车辆行驶状态复杂,交通噪声污染极为突出。选取深圳市典型的高架复合道路——春风高架和爱国高架进行实地监测,同时运用SoundPLAN软件模拟其噪声污染现状与安装声屏障后的降噪效果。根据监测模拟结果,从合理进行道路规划、装设声屏障和铺设低噪声路面等方面提出高架复合道路噪声污染控制的对策建议。     

低噪声路面降噪效果研究

通过对公路交通噪声特征,低噪声路面的特点、结构、降噪机理及国内外研究现状的分析,对宁杭高速二期工程低噪声路面与普通路面噪声监测结果进行对比分析,确认低噪声沥青路面具有比较明显的降噪效果,路肩处噪声可降低3～4 dB(A),路外15 m处可降低1.1～3.5 dB(A).     

城市道路交通噪声分布模拟研究

通过对梅州市中心城区7条道路的噪声监测,分析了中心城区道路的噪声污染水平。采用道路交通噪声预测模型,以实测交通流数据对中心城区的噪声污染进行模拟和减噪措施评估。结果表明,采用限速措施和安装声屏障措施均有降低噪声污染的效果,为管理部门防治噪声污染提供了参考。     

一种室外声屏障过渡区域绕射衰减测量方法

提出了一种声屏障声影区与声亮区过渡区域的绕射衰减室外测量方法。方法采用5ms的正弦波作为测试信号,利用声波到达时间的差异有效地排除地面反射和有限长声屏障两侧绕射的影响,并通过背景噪声频谱分析选取测试声以及对接受信号FIR滤波以最大限度降低背景噪声的影响,同时考虑了气象条件变化导致的大气衰减修正。为进一步验证方法有效性,选取直立声屏障作为试验案例。结果表明,与室内全消声室试验结果、几何绕射理论结果接近,试验精度高。     

居住区的交通噪声问题及防治方法

首先分析交通噪声对居住区声环境的影响及当前存在的问题，然后重点探讨相应的防治方法，特别是在居住区的规划中，以对噪声不敏感的建筑物和利用绿化隔离带形成小区周边的声屏障、小区道路系统防止城市交通穿越、加强住宅建筑设计中隔声构造处理等方面提出了具体的技术措施．     

铁路交通噪声对鸟类生态环境的影响预测评价

由于鸟类的听觉频率范围与人类不同，以往基于A计权声压级的噪声测量方法，用于鸟类声环境的监测评价并不准确。以广东省江门市新会区“小鸟天堂”风景名胜区为例，开展铁路交通噪声对鸟类生态环境的影响研究。首先，通过实地调查，对鸟类生态区的多个监测点进行声环境线性频谱测量；其次，根据新茂铁路新会段的规划布局，采用模式预测法计算铁路运行期间在监测点产生的交通噪声频谱，并与铁路运行前实地测量的现状频谱叠加；在此基础上，进一步探讨铁路交通噪声对鸟类生态区声环境的影响以及预防措施。研究结果表明，列车运行时在鸟类良好听觉频率范围的噪声增量可达10~30dB，将严重影响鸟类声环境；当采取全封闭声屏障防护措施之后，可有效降低“小鸟天堂”景区范围的噪声。     

重庆市道路交通噪声分布规律及控制措施研究

监测重庆市主城区道路旁居民住宅不同楼层昼间交通噪声等效声级,并分析其垂直分布规律。结果表明,随测点与地面高差的增加,噪声呈先增加后减小的趋势。隔声效果监测结果表明,隔声屏在重庆典型山城的地理环境下隔声效果较差,隔声窗具有较好的隔声效果,且测点距离越近隔声效果越明显。     

北京城市声环境自动监测系统监测点位布设方法初探

噪声自动监测相对手工监测而言,更能真实反映城市声环境质量,随着噪声自动监测技术的不断完善,自动监测替代手工监测已成为必然趋势.但目前我国城市声环境自动监测系统正处于起步阶段,国内还没有对声环境自动监测系统的点位布设提出成熟、合理的方案.文章结合北京市声环境自动监测系统建设的实际工作情况,对监测系统总体框架、自动监测点位布设的原则及方法等进行了阐述并提出近期需要解决的问题.     

国内外环境噪声监测方法比较及启示

综合比较了中国、日本、欧盟、美国和澳大利亚等国家或地区的环境噪声监测与评价方法,分析了声环境质量监测法、噪声地图预测法和噪声源监测法3种环境噪声评估方法的优缺点,认为声环境质量监测法适合现阶段中国环境噪声监测与管理需求,但下一步应结合噪声产生与传播预测方法改进中国声环境监测评价方法,增强对监测过程的质控,增加重点噪声源监测,以期更全面地反映城市声环境质量状况。     

南京市快速道路交通噪声污染调查

对南京市城西干道凤台路、虎踞北路双层高架道路交通噪声进行了测量.结果表明,城西干道两侧30m范围内夜间噪声严重超标.建议今后在建设城市快速道路时,地面路段两侧可种植绿化隔离带,高架路段设置隔声屏障;不具备条件的可为临街住户安装隔声门窗,以保护道路两侧的居住环境.     

变压器噪声对居民室内噪声影响分析和控制

变压器噪声对居民室内的影响，往往是通过建筑物固体传声和结构辐射噪声所引起，采取以隔振为主要控制手段的噪声治理措施，可以取得较为满意的降噪效果。     

A comparative study of noise pollution levels in some selected areas in Ilorin Metropolis, Nigeria

The noise pollution is a major problem for the quality of life in urban areas. This study was conducted to compare the noise pollution levels at busy roads/road junctions, passengers loading parks, commercial, industrial and residential areas in Ilorin metropolis. A total number of 47-locations were selected within the metropolis. Statistical analysis shows significant difference (P < 0.05) in noise pollution levels between industrial areas and low density residential areas, industrial areas and high density areas, industrial areas and passengers loading parks, industrial areas and commercial areas, busy roads/road junctions and low density areas, passengers loading parks and commercial areas and commercial areas and low density areas. There is no significant difference (P > 0.05) in noise pollution levels between industrial areas and busy roads/road junctions, busy roads/road junctions and high density areas, busy roads/road junctions and passengers loading parks, busy roads/road junctions and commercial areas, passengers loading parks and high density areas, passengers loading parks and commercial areas and commercial areas and high density areas. The results show that Industrial areas have the highest noise pollution levels (110.2 dB(A)) followed by busy roads/Road junctions (91.5 dB(A)), Passengers loading parks (87.8 dB(A)) and Commercial areas (84.4 dB(A)). The noise pollution levels in Ilorin metropolis exceeded the recommended level by WHO at 34 of 47 measuring points. It can be concluded that the city is environmentally noise polluted and road traffic and industrial machineries are the major sources of it. Noting the noise emission standards, technical control measures, planning and promoting the citizens awareness about the high noise risk may help to relieve the noise problem in the metropolis.     

Spatial variations in pedestrian soundscape evaluation of traffic noise

Walking is necessary for experiencing urban space, but pedestrians are seriously disturbed by traffic noise. This study aimed to clarify spatial variations in soundscape evaluation in pedestrian spaces used solely for walking, including traffic noise annoyance, the dominance of various sound sources, and the perceptual dimensions of the soundscape. Three traffic noise level areas, at various distances from the road, were evaluated in a typical pedestrian space in China, using a questionnaire survey in an on-site study. The results reveal that, first, the soundscape evaluations in the high-noise area (70 dBA) and middle-noise area (60 dBA) are more similar, but present a larger difference with the low-noise area (50 dBA). The latter is more complicated, and more subjective evaluations in this area are required than for higher sound-level areas. Second, the correlation between the soundscape evaluations of the middle-noise area and the low-noise area demonstrates more similarity, but presents a larger difference with the high-noise area, meaning the effectiveness in the high-noise area may differ from lower sound level areas even with the same soundscape improvement measures. Finally, the relationship of the dominance of natural sound with other soundscape evaluations become weaker as the distance from the road increases; this means that deliberately increasing natural sound might be an effective method to improve the soundscape quality in the high-noise area. These findings can provide a reference for soundscape evaluations and landscape design in pedestrian spaces where traffic noise is a problem.     

Degradation of natural habitats by roads: Comparing land-take and noise effect zone

Roads may act as barriers, negatively influencing the movement of animals, thereby causing disruption in landscapes. Roads cause habitat loss and fragmentation not only through their physical occupation, but also through traffic noise. The aim of this study is to provide a method to quantify the habitat degradation including habitat loss and fragmentation due to road traffic noise and to compare it with those of road land-take. Two types of fragmentation effects are determined: structural fragmentation (based on road land-take only), and functional fragmentation (noise effect zone fragmentation, buffer using a threshold of 40 dB). Noise propagation for roads with a traffic volume of more than 1000 vehicles per day was simulated by Calculation of Road Traffic Noise (CRTN) model. Habitat loss and fragmentation through land-take and noise effect zone were calculated and compared in Zagros Mountains in western Iran. The study area is characterized by three main habitat types (oak forest, scattered woodland and temperate grassland) which host endangered and protected wildlife species. Due to topographic conditions, land cover type, and the traffic volume in the region, the noise effect zone ranged from 50 to 2000 m which covers 18.3% (i.e. 516,929.95 ha) of the total study area. The results showed that the habitat loss due to noise effect zone is dramatically higher than that due to road land-take only (35% versus 1.04% of the total area). Temperate grasslands lost the highest proportion of the original area by both land-take and noise effect zone, but most area was lost in scattered woodland as compared to the other two habitat types. The results showed that considering the noise effect zone for habitat fragmentation resulted in an increase of 25.8% of the area affected (316,810 ha) as compared to using the land-take only (555,874 ha vs. 239,064 ha, respectively). The results revealed that the degree of habitat fragmentation is increasing by considering the noise effect zone. We conclude that, although the roads are breaking apart the patches by land-take, road noise not only dissects habitat patches but takes much larger proportions of or even functionally eliminates entire patches.     

Assessment of Traffic Noise Pollution from 1989 to 2003 in Lanzhou City

On the basis of the continuous traffic noise data observed at 142 sites distributed in 52 roads from 1989 to 2003, the characteristics of traffic noise and effect factors were analyzed through traffic noise indices, such as Lep, L10, L50, L90, TNI, and Pn. Our findings allow us to reach a number of conclusions as follows: Firstly, traffic noise pollution was serious, and its fluctuant characteristic was obvious, resulting in a great intrusion to public in Lanzhou City during last 15 years. Secondly, traffic noise made a distinction between trunk lines and secondary lines, west-east direction roads and north-south direction roads. Thirdly, spatial character and time rule of traffic noise were obvious. In addition, traffic volume, traffic composition, road condition, and traffic management were identified as the key factors influencing traffic noise in this city.