声屏障声学设计和测量规范

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1^# 大中小发表于 2007-11-28 10:02 只看该作者

声屏障声学设计和测量规范

中华人民共和国环境保护行业标准<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com

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HJ／T90—2004<o:p></o:p>

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声屏障声学设计和测量规范! ~9 g3 b9 w9 _
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Norm on Acoustical Design and Measurement of Noise Barriers 

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<v:line id=_x0000_s1027 style="Z-INDEX: 2; LEFT: 0px; POSITION: absolute; TEXT-ALIGN: left" to="423pt,31.2pt" from="0,31.2pt"></v:line>2004—07—12发布 2004—10—01实施<o:p></o:p>4 k& }6 @8 I9 p6 I; g5 F3 M1 A$ n

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国家环境保护总局 发布
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目次<o:p></o:p>
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前言<o:p></o:p>$ O/ d8 Z; N1 @! V4 L& d) n2 C

1．主题内容与适用范围………………………………………………………………1<o:p></o:p>1 i+ {" s! r3 j! W- \
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2．规范性引用文件……………………………………………………………………1<o:p></o:p>- N) F& B( j8 y) n
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3．名词术语……………………………………………………………………………1<o:p></o:p>5 B8 A7 X* x( b4 o8 I \

4．声屏障的声学设计…………………………………………………………………3<o:p></o:p>/ G5 B2 B, f" T) A0 \
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5．声屏障声学性能的测量方法…………………………………………………… 13<o:p></o:p> J( Q F5 k, ` u
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6．声屏障工程的环保验收…………………………………………………………20<o:p></o:p>, q( ?' Q+ i G' j+ [& c# [* }
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附录A(规范性附录)反射声修正量△Lr的计算……………………………………22<o:p></o:p>
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附录B(规范性附录)等效频率fe的计算……………………………………………26<o:p></o:p>

附录C(资料性附录)参考文献………………………………………………………27<o:p></o:p>

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前言

为了贯彻执行《中华人民共和国环境噪声污染防治法》第36条“建设经过已有的噪声敏感建筑物集中区域的高速公路和城市高架、轻轨道路，有可能造成环境污染的，应当设置声屏障或者采取其他有效的控制环境噪声污染的措施”，制订本规范。<o:p></o:p>" `% x8 ^: {: i4 { T$ m
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本规范规定了声屏障的声学设计和声学性能的测量方法。<o:p></o:p>; F" H$ j0 M- Q. V" i2 X/ p9 j8 z. x

本规范的附录A、B是规范性附录。附录C是资料性附录。<o:p></o:p>

本规范由国家环境保护总局科技标准司提出并归口。<o:p></o:p>

本规范起草单位：中国科学院声学研究所、同济大学声学研究所、北京市劳动保护科学研究所、福建省环境监测中心。<o:p></o:p>
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参加单位：青岛海洋大学物理系、北京市环境监测中心、上海市环境科学研究院、天津市环境监测中心、上海申华声学装备有限公司、上海市环保科技咨询服务中心、宜兴南方吸音器材厂、北京市政工程机械厂。<o:p></o:p>
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本规范由国家环境保护总局负责解释。<o:p></o:p>

本规范2004年10月1日起实施。<o:p></o:p> 

1 主题内容与适用范围<o:p></o:p>
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1．1 本规范规定了声屏障的声学设计和声学性能的测量方法。<o:p></o:p>

1．2 本规范主要适用于城市道路与轨道交通等工程，公路、铁路等其他户外场所的声屏障也可参照本规范。<o:p></o:p>3 G2 g9 C( q7 _0 V9 m
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2 规范性引用文件<o:p></o:p>. M5 x: J+ Z7 a) Z8 c

下列标准和规范中的条款通过在本规范中引用而构成本规范的条款，与本规范同效。<o:p></o:p>, y' K. w- H9 }: H3 [8 U

GBJ005—96 公路建设项目环境影响评价规范<o:p></o:p>% _: x! H4 T2 ?# ]& V5 @
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GBJ47—83 混响室法—吸声系数的测量方法<o:p></o:p>& C {3 r( Z" I0 J- L' S
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GBJ75—84 建筑隔声测量规范<o:p></o:p>* @4 v7 k4 I9 @2 {

GB3096—93 城市区域环境噪声标准<o:p></o:p>

GB3785—83 声级计<o:p></o:p>
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GB／T3947—1996 声学名词术语<o:p></o:p>

GB／T14623—93 城市区域环境噪声测量方法<o:p></o:p>
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GB／T15173—94 声校准器<o:p></o:p>
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GB／T17181—1999 积分平均声级计<o:p></o:p>

HJ／T2.4—95 环境影响评价技术导则—声环境<o:p></o:p>
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当上述标准和规范被修订时，应使用其最新版本。6 a& S; u4 d2 [, i$ x
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3 名词术语

本规范采用下列名词定义<o:p></o:p>

3．1 声压级 (Lp

sound pressure level<o:p></o:p>5 q8 s2 Y2 A6 J4 ~. ^

声压与基准声压之比的以10为底的对数乘以20，单位为分贝(dB)：<o:p></o:p>
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le="" type="#_x0000_t75"><v:imagedata o:title="" src="file:///C:\DOCUME~1\user\LOCALS~1\Temp\msohtml1\01\clip_image002.wmz"></v:imagedata></v:shape> dB (1)

式中： p—声压，Pa<o:p></o:p>% Y! N+ A' I5 z, Q# ~( H8 A

p0—基准声压， 20μPa

3．<?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" /><st1:chmetcnv w:st="on" TCSC="0" NumberType="1" Negative="False" HasSpace="True" SourceValue="2" UnitName="a">2 A</st1:chmetcnv>计权声［压］级(LpA,LA

A-weighted sound[ pressure] level<o:p></o:p>. \( O, G# P" U4 q3 {% c$ e6 T5 F4 ~
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用A计权网络测得的声压级。* K |* |. D2 C* ]) q2 B

3．3 等效［连续A计权］声［压］级 (LAeq,T，Leq

equivalent ［A-weighted continuous］sound ［pressure］ level<o:p></o:p>

在规定时间内，某一连续稳态声的A［计权］声压，具有与随时间变化的噪声相同的均方A［计权］声压，则这一连续稳态声的声级就是此时变噪声的等效声级，单位为分贝(dB)。<o:p></o:p>+ p6 T* D3 k0 g( E+ ~5 u

等效声级的公式是<o:p></o:p>6 z* I: G5 g+ `7 d# i" x
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式中：LAeq,T—等效声级，dB<o:p></o:p>* `5 p: d4 d! a g$ y l5 Z" n
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T—指定的测量时间,<o:p></o:p>. W+ G. E+ @; y) r6 I
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 pA(t)—噪声瞬时A［计权］声压，Pa<o:p></o:p>

p0—基准声压，20μPa <o:p></o:p>1 C0 {5 l& W0 ?0 ]: o U8 n

当A［计权］声压用A声级LpA (dB)表示时，则此公式为( j+ a& \3 r3 Z" k, B7 D4 J
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3．4 最大声[压]级(Lpmax) maximum sound [pressure] level<o:p></o:p>
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在一定的测量时间内，用声级计快档(F)或慢档(S)测量到的最大A计权声级、倍频带声压级或1／3倍频带声压级。<o:p></o:p>
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3．5 背景噪声 background noise<o:p></o:p>
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当测量对象的声信号不存在时，在参考点位置或受声点位置测量的噪声。本规范中所指的测量对象一般指采用声屏障来控制的噪声源。<o:p></o:p>7 g# h4 O/ [. ^/ M4 J5 G
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3．6 声屏障 noise barriers<o:p></o:p>
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一种专门设计的立于噪声源和受声点之间的声学障板，它通常是针对某一特定声源和特定保护位置(或区域)设计的。<o:p></o:p>
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3．7 声屏障插入损失(IL) insertion loss of noise barriers<o:p></o:p>6 |+ U5 @% P4 K( i5 N9 V. r/ l8 V
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在保持噪声源、地形、地貌、地面和气象条件不变情况下安装声屏障前后在某特定位置上的声压级之差。声屏障的插入损失，要注明频带宽度、频率计权和时间计权特性。例如声屏障的等效连续A计权插入损失表示为ILPAeq。<o:p></o:p>

3．8 吸声系数(α) sound absorption coefficient<o:p></o:p>7 D2 N& U# Q3 k4 g: Q! p

在给定的频率和条件下，分界面(表面)或媒质吸收的声功率，加上经过界面(墙或间壁等)透射的声功率所得的和数，与入射声功率之比。一般其测量条件和频率应加说明。吸声系数等于损耗系数与透射系数之和。<o:p></o:p> K$ r4 x4 q% e+ L9 u
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3．9 降噪系数(NRC) noise reduction coefficient<o:p></o:p>7 @9 Y/ S5 l" V5 w& Z/ s

在250、500、1000、2000Hz测得的吸声系数的平均值，算到小数点后两位，末位取0或5。<o:p></o:p>
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3．10 传声损失(TL) sound transmission loss<o:p></o:p>
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屏障或其它隔声构件的入射声能和透射声能之比的对数乘以10，单位是分贝：<o:p></o:p>

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式中：Ei—入射声能；<o:p></o:p>
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Et—透射声能。<o:p></o:p>
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3．11 计权隔声量(Rw) weighted sound reduction index<o:p></o:p>% ~, q' E# O6 e' Q5 b9 H. _

隔声构件空气声传声损失的单一值评价量，它是由100～3150Hz的1/3倍频带的传声损失推导计算出来的。<o:p></o:p>2 H. v) d( P; E. |
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声屏障的设计中，为避免由声屏障透射声能量影响声屏障的实际降噪效果，通常采用具有一定传声损失的结构。声屏障的空气声隔声量可采用100～3150Hz 1/3倍频带的平均隔声量或计权隔声量来评价。<o:p></o:p>2 w% q; C' c. j( d

4 声屏障的声学设计<o:p></o:p>

声屏障是降低地面运输噪声的有效措施之一。一般3～6m高的声屏障，其声影区内降噪效果在5～12dB之间。<o:p></o:p>
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4．1 声学原理<o:p></o:p>
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当噪声源发出的声波碰到声屏障时，它将沿着三条路径传播(见图1.a)：一部分越过声屏障顶端绕射到达受声点；一部分穿透声屏障到达受声点；一部分在声屏障壁面上产生反射。声屏障的插入损失主要取决于声源发出的声波沿这三条路径传播的声能分配。<o:p></o:p>
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4．1．1 绕射<o:p></o:p> Q; V( R- z- i

越过声屏障顶端绕射到达受声点的声能比没有屏障时的直达声能小。直达声与绕射声的声级之差，称之为绕射声衰减，其值用符号△Ld表示，并随着Φ角的增大而增大(见图1.b)。声屏障的绕射声衰减是声源、受声点与声屏障三者几何关系和频率的函数，它是决定声屏障插入损失的主要物理量。<o:p></o:p>

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图1 声屏障绕射、反射路径图! m; f) t+ F' u# f

<o:p> </o:p>9 J2 Q% @, U! O6 @) K, C' T) W) @6 r
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4．1．2 透射<o:p></o:p>* W4 i: s, C( r" }

声源发出的声波透过声屏障传播到受声点的现象。穿透声屏障的声能量取决于声屏障的面密度、入射角及声波的频率。声屏障隔声的能力用传声损失TL来评价。TL大，透射的声能小；TL小，则透射的声能大，透射的声能可能减少声屏障的插入损失，透射引起的插入损失的降低量称为透射声修正量。用符号ΔLt表示。通常在声学设计时，要求TL—△Ld≥10dB，此时透射的声能可以忽略不计，即△Lt≈0。<o:p></o:p>, }/ o- p+ L0 `" E/ Y( q

4．1．3 反射<o:p></o:p>( _6 V: N& ^. X
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当道路两侧均建有声屏障，且声屏障平行时，声波将在声屏障间多次反射，并越过声屏障顶端绕射到受声点，它将会降低声屏障的插入损失(见图1.c)，由反射声波引起的插入损失的降低量称之为反射声修正量，用符号△Lr表示。<o:p></o:p>

为减小反射声，一般在声屏障靠道路一侧附加吸声结构。反射声能的大小取决于吸声结构的吸声系数α，它是频率的函数，为评价声屏障吸声结构的整体吸声效果，通常采用降噪系数NRC。<o:p></o:p>1 v. O4 i# W# z- p6 Z
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4．2 声屏障插入损失计算<o:p></o:p>

4．2．1 绕射声衰减△Ld的计算<o:p></o:p>+ g) a2 ?1 o2 d5 ~1 z8 `8 T

4．2．1．1 点声源<o:p></o:p>
9 x! j/ f" \4 G0 S- p3 y& X) I M M
当线声源的长度远远小于声源至受声点的距离时(声源至受声点的距离大于线声源长度的3倍)，可以看成点声源，对一无限长声屏障，点声源的绕射声衰减为：

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 0 dB , N ≤—0.2<o:p></o:p>

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N—菲涅耳数，<v:shape id=_x0000_i1038 style="WIDTH: 99.75pt; HEIGHT: 30.75pt" o:ole="" type="#_x0000_t75"> <v:imagedata o:title="" src="file:///C:\DOCUME~1\user\LOCALS~1\Temp\msohtml1\01\clip_image024.wmz"></v:imagedata></v:shape><o:p></o:p>5 z% A. H: Y5 {% j" T% @0 {$ x

λ—声波波长，m<o:p></o:p>; Y" ?; R ^# l0 R l, M
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d—声源与受声点间的直线距离，m<o:p></o:p>
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A—声源至声屏障顶端的距离，m<o:p></o:p>: [$ h: c; d/ o- L$ K
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B—受声点至声屏障顶端的距离，m<o:p></o:p>
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若声源与受声点的连线和声屏障法线之间有一角度β时，则菲涅耳数应为<o:p></o:p>
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N(β)=Ncosβ<o:p></o:p>: P2 N: `7 [+ A h5 G1 Q

工程设计中，△Ld可从图2求得<o:p></o:p>

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图2 声屏障的绕射声衰减曲线4 X: o5 t8 Q9 o1 o! u
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4．2．1．2 无限长线声源，无限长声屏障

当声源为一无限长不相干线声源时，其绕射声衰减为：<o:p></o:p>

 
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