地铁车站敷设方式对站台噪声特性的影响

为研究不同车站敷设方式对站台噪声特性的影响,选取同一线路相同站台型式的地下站及高架站展开现场噪声测试,根据列车进、出站时站台噪声水平、站台环境噪声水平及站台背景噪声水平分析车站敷设方式对站台噪声的影响,并根据噪声频谱特性分析两个站台噪声特性的差异。结果表明,两个站台在列车进(出)站时站台进(出)站端等效连续A声级LAeq存在大于现行标准限值80 dB(A)情况,站台中部噪声则始终低于标准限值。列车进、出站引起的地下站台噪声水平略高于高架站站台,其中列车进、出站时LAeq大约为0.3 dB(A)至2.1 dB(A),环境噪声水平LAeq,1h大约为0.8 dB(A)至1.1 dB(A),但无车无广播时高架站站台背景噪声略大于地下站台,大约为1.9 dB(A)。从列车进、出站站台时噪声频谱特性来看,200 Hz以下,两站台噪声峰值频率存在显著差异,高架站台出现在25 Hz至50 Hz,地下站台出现在50 Hz至100 Hz,主要由站台结构振动引起;200 Hz以上,两类站台噪声频谱分布规律基本一致,高架站声压级略小于地下站台,平均小2.0 dB(A)至3.8 d B(A)。建议根据不同敷设方式的车站的结构特性及站台空间形式采取噪声控制措施。

Influences of Metro Station Layout Modes on Platform Noise Characteristics

The noise status and characteristics of metro station platform with different station layout modes was studied.The field tests of noise of underground stations and elevated stations with the same platform type were conducted on the same line.According to the noise level induced by the trains’arrival and departure,platform environment noise level and platform background noise level without trains’passing,the influence of station layout modes on platform noise was analyzed.And the difference of noise spectrum characteristics between the two platforms were analyzed.The results show that the equivalent continuous A-weighted sound pressure levels(LAeq)at both ends of two platforms with the trains’arrival and departure exceed the standard limit of 80 dB(A),while the noise in the middle of the platforms are always lower than the standard limit.The noise level of underground station is slightly larger than that of elevated station platform.The LAeq caused by trains’arrival and departure in underground station platform is about 0.3 dB(A)-2.1 dB(A)higher than inelevated station.While the environmental noise level(an hour equivalent continuous A-weighted sound pressure level)LAeq,1h is about 0.8-1.1 dB(A).However,the background noise in the elevated station platform is about 1.9 dB(A)larger than that in the underground platform.From the viewpoint of noise spectrum characteristics with trains’arrival and departure,there is a significant difference of the noise peak frequencies between the two platforms below 200 Hz.The noise spectrum peak of the elevated platform appears at 25 Hz-50 Hz,while the peak of the underground platform appears at 50 Hz-100 Hz,which mainly radiated by platform structure vibration.The noise spectrum distribution rules of the two stations are basically the same above 200 Hz,and the sound pressure level of the elevated station is about 2.0 dB(A)-3.8 dB(A),smaller than that of the underground platform.It is suggested that noise control measures on platforms should be taken into consideration according to the structure characteristic and platform spatial form of different station layout modes.