成都地铁2号线高架段噪声特性研究

发布时间：2018-05-29 08:27

本文选题：成都地铁2号线 + 高架桥　；参考：《西南交通大学》2017年硕士论文

【摘要】：近年来,随着城市规模的扩大,城市轨道交通蓬勃发展,以其高速快捷、运输量大、舒适安全、空间利用率高、环境污染低等优势成为人们日常出行最重要的交通方式之一。城市轨道交通在带给人们便利的同时,引发的噪声振动问题给沿线人们的工作和生活带来的影响也越来越大。高架线在城市轨道交通线路中所占的比例很大,因而其周围的噪声影响也日益引起人们的关注。本文采用理论分析、软件预测和现场实测相结合的方法研究成都地铁2号线高架桥段环境噪声。在深入学习分析国内外铁路及城市轨道交通噪声资料的基础上,对地铁2号线高架段环境噪声进行现场实测,验证了噪声预测软件Cadna/A的适用性,分析了测试截面环境噪声的传播规律,探讨了高架线路附近环境噪声和结构噪声的特性。本文的主要结论如下:1.根据实测噪声信号数据计算出各测点的等效连续A声级,拟合出成都地铁2号线高架段环境噪声的水平方向上辐射衰减公式,可用于相似情形的环境噪声模拟。2.用Cadna/A软件对实测场景的环境噪声进行模拟,并在成都地铁2号线高架段进行环境噪声现场实测,将预测与实测结果进行对比分析。结果表明:在轨面以下距近轨中心线20 m的范围内,软件预测效果较差,适用性不强;20 m以外的预测值较准确,软件在该范围的预测结果具有可靠性。3.在列车通过时段内,各测点环境噪声和结构噪声的声压幅值变化规律一致:垂直方向上,距近轨中心线7.5 m处的测点噪声声压幅值随垂直高度的降低呈衰减趋势;水平方向上,测点噪声声压幅值随测点水平距离的增加而降低。4.列车通过时测点环境噪声主要频率范围都在1000 Hz以下,且最优频率分布集中;各测点环境噪声声压级均在800 Hz处达到最大值。结构噪声主要频率范围为50～120 Hz,最优频率分布集中;各测点结构噪声声压级在80 Hz或100 Hz处达到最大值。5.高架桥梁体影响了列车声源的辐射,在桥梁附近对噪声的传播规律有较大影响。由于梁体对直达声源的遮蔽作用及桥梁结构自身的二次结构噪声使得梁体附近的噪声分布情况较为复杂,而在距桥体较远处,环境噪声受梁体的干扰较小。
[Abstract]:In recent years, with the expansion of urban scale, urban rail transit is booming. With its high speed, large volume of transport, comfortable and safe, high utilization of space, low environmental pollution and other advantages, urban rail transit has become one of the most important means of transportation. At the same time, the noise and vibration caused by urban rail transit bring more and more influence to the work and life of people along the route. The viaduct accounts for a large proportion of urban rail transit lines, so the influence of noise around it is attracting more and more attention. In this paper, the environmental noise of the viaduct section of Chengdu Metro Line 2 is studied by combining theoretical analysis, software prediction and field measurement. On the basis of deeply studying and analyzing the noise data of railway and urban rail transit at home and abroad, the environmental noise of the elevated section of Metro Line 2 is measured on the spot, and the applicability of the noise prediction software Cadna/A is verified. The propagation law of environmental noise in test section is analyzed, and the characteristics of environmental noise and structural noise near elevated lines are discussed. The main conclusions of this paper are as follows: 1: 1. According to the measured noise signal data, the equivalent continuous A sound level of each measuring point is calculated, and the radiation attenuation formula in horizontal direction of the environmental noise in the elevated section of Chengdu Metro Line 2 is fitted, which can be used to simulate the environmental noise in similar cases. The environmental noise of the measured scene is simulated by Cadna/A software, and the environmental noise is measured in the elevated section of Chengdu Metro Line 2. The prediction results are compared with the measured results. The results show that in the range of 20 m below the orbit surface, the prediction results of the software are poor, and the prediction values beyond 20 m are more accurate. The prediction results of the software in this range are reliable. 3. During the passing period of the train, the sound pressure amplitude of ambient noise and structural noise at each measuring point is the same: in the vertical direction, the sound pressure amplitude of the measuring point at 7.5 m near the central line of the rail decreases with the decrease of the vertical height; in the horizontal direction, the sound pressure amplitude of the measuring point decreases with the decrease of the vertical height. The amplitude of noise sound pressure decreases with the increase of horizontal distance. The main frequency range of ambient noise is below 1000 Hz, and the optimal frequency distribution is concentrated, and the sound pressure level of ambient noise at each measuring point reaches the maximum at 800Hz. The main frequency range of structural noise is 50 ~ 120 Hz, the optimal frequency distribution is concentrated, and the sound pressure level of structural noise at 80 Hz or 100 Hz reaches the maximum value of .5. Viaduct beam affects the radiation of train sound source, and has great influence on the propagation of noise near the bridge. Because of the shielding effect of beam body to direct sound source and the secondary structure noise of bridge structure, the distribution of noise near beam body is more complicated, but in the distance from bridge body, the environmental noise is less disturbed by beam body.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X839.1;TB53

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