輕軌運輸系統噪音預測模式與防制對策之研究

Abstract

摘 要 輕軌運輸系統其建造成本低於捷運、建設時程短之優勢，系統彈性可以C型路權之輕軌行人步區或混合路權與其他車輛共用平面車道，亦可採A型路權之輕軌捷運系統提升營運效率。未來輕軌運輸系統之引進，不管採何種路權方式營運，噪音衝擊將對沿線居民生活起居造成影響。俟於國內未有建設完成之輕軌運輸系統，以香港輕軌運輸系統做為本研究之監測對象，經本研究所推估出輕軌噪音預測模式如下： 無背景音源之輕軌噪音預測模式： Leq=(1.016)*Lmax+(0.770)*10log{[R(1.5D+d)]/v}-31.09 D：受音點與軌道中心之距離 d：列車長度 Leq：小時均能音量 Lmax：列車通過最大音量 R：列車通過班次數 v：列車行駛速率 在固定背景音源下之輕軌噪音預測模式： Leq=(1.865)*10log{[I’/I0(Ta+Tf+ΣTi-1)+ΣniAj]/T}-49.61 d：受音點距軌道最近之距離(公尺) I0/I’：背景音源 Lmaxj：第j種列車通過時所產生之最大音量 lj：第j種列車之長度(公尺) nj：第j種列車通過的列車數 (Tr)j：受音點受第j種列車噪音影響的總時間(秒) Ta,Tf,Ti-1：接收到背景音源的時間 vj：第j種列車之行駛速度(公尺/秒) 關鍵詞：輕軌運輸系統、噪音預測模式

Abstract The characteristics of LRT were lower cost and shorter construction period than MRT; besides LRT can operate with other traffic on non-exclusive way and with pedestrian on LRT/Pedestrian Mall, and also can operate on the exclusive way to improve the efficiency of LRT. Introducing LRT system the noise must affect the residents’ life that lived along the LRT line. There is no LRT system in Taiwan, this study establishes the prediction model by case study of the LRT system in Hong Kong, the result will be as follow: Without Background Sound Level: Leq=(1.016)*Lmax+(0.770)*10log{[R(1.5D+d)]/v}-31.09 R: number of trains per hour D: distance of the receive from the track centerline in meters d: average train length in meters v: train speed in km/hr With fixed Background Sound Level: Leq=(1.865)*10log{[I’/I0(Ta+Tf+ΣTi-1)+ΣniAj]/T}-49.61 d: the shortest distance between receiver and track in meters I0/I’: background sound level Lmaxj: the maximum noise level produced by passing train j lj: length of passing train j in meters nj: the numbers of the passing train j (Tr)j : the total affected period of the passing train Ta,Tf,Ti-1: the total affected period of the background sound level vj: the speed of the passing train j (m/s)

Key words: Light Rail Transit, prediction model of noise