Community response to Shinkansen noise and vibration: a survey in areas along the Sanyo Shinkansen Line

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1 Community response to noise and vibration: a survey in areas along the Sanyo Line Takashi Yano Kumamoto University, Kurokami, , Kumamoto , Japan, yano@gpo.kumamoto-u.ac.jp, Takashi Morihara Ishikawa National College of Technology, Tsubata cho Kitanakajo, Kawakita , Japan, morihara@ishikawa-nct.ac.jp, Tetsumi Sato Hokkai Gakuen University, Chuo -ku Minami 26 Nishi , Sapporo , Japan, sato@arc.hokkai-s-u.ac.jp, A social survey on community response to noise was carried out in areas along the Sanyo Line in The sample size was 724 and the response rate was 66%. Since the noise barriers were constructed along the railway, the noise level was less than about 50 db L Aeq,24h. The relationships between L Aeq,24h and % highly annoyed for general noise annoyance and various activity interferences caused by the were compared with those for conventional which were found in data collected in the same area in It has been reported that noise is more annoying than conventional railway noise. However, the reason is not yet clear. In the present study general noise annoyance and annoyance caused by vibration from the were also significantly greater at the same noise level than those of conventional. However, the other activity interferences were almost the same between both sources. It was hypothesized that vibration was more than conventional and that the vibration increased the noise annoyance more than conventional. In 2004, the measurements of vibrations from the and conventional railway were conducted in the same area to estimate the vibration exposure to each house. As a result it was found that the vibration levels from were significantly higher than those from conventional. Thus, the above hypothesis regarding the importance of vibration on noise annoyance was verified. 1 Introduction In 1964, the first super express railway in the world, the Tokaido Line, was opened between Tokyo and Osaka. In 1975, the Sanyo Line was opened between Osaka and Fukuoka, Kyushu Island. Afterwards, lines have been developed in the northern part of Honshu and in Kyushu. Nowadays such super express have constructed in Europe and Korea and are going to be constructed in the other Asian countries. The emits much noise and vibration because of its high speed. The noise problem caused by such super express has grown from a local to a global issue. Several social surveys on community response to noise have been carried out so far in Japan. Sone et al [1] conducted social surveys on noise in areas along the New Tokaido and Sanyo Lines, compared the results with aircrafts and discussed the application of several noise indices to evaluate noise annoyance. Afterwards Machida [2] showed the importance of the number of events, that is, the superiority of L Aeq,24h to L Amax as the noise index, from social surveys in seven areas along New Tokaido, Sanyo, Tohoku and Joetsu Lines. Both studies also pointed out the importance of vibration on noise annoyance from people s subjective responses. Tamura [3] compared the community response to noise with conventional railway noise and indicated that noise was more annoying than conventional railway noise. Multivariate analysis found that people living along the did not recognize the benefits of the noise source and had severe attitudes to the source while people living along conventional felt the source necessary and had moderate attitudes. Such differences in attitudes seemed to affect noise annoyance. Yokoshima et al [4] constructed a path model of vibration annoyance caused by and showed factors affecting the annoyance. Sato [5] discussed the effects of vibration on road traffic and railway noise annoyance and found higher annoyance in areas with more vibration exposure in both road traffic and railway surveys. In order to accumulate data on community response to noise considering the developing network in Japan a social survey on community response to noise was carried out in areas along the New Sanyo Line in Kyushu, In the present study the responses were compared with those to conventional obtained in 2002 and the difference in annoyance between and conventional railway noises was discussed focusing on the effect of vibration exposures from both sources. 1837

2 2 Method 2.1 Social surveys A social survey on community response to noise was carried out in areas along the Sanyo Line in Fukuoka Prefecture, in Since the line was elevated and noise barriers were constructed along the line in almost all areas, basically all the detached houses within 150 m of the railway were selected for the survey (see Figure 1). When there was no house within the 150 m range, only detached houses directly facing the railway were also selected, of which a house was 680 m apart from the railway at the maximum. Respondents, from 20 to 75 years of age, were randomly selected from a list of voters on a one-person-per-family basis. The questionnaires were distributed and collected either by the staff or by mail. Totally, 724 responses were obtained and the response rate was 66%. Figure 1 Photo of a survey site The total number of passing trains per day was 180. There was no train during night time from 0 to 6 am. The speed was about 200 km/h. Almost the same social survey on community response to conventional railway noise was conducted in the areas along four lines in Fukuoka Prefecture. Since the conventional railway was constructed on the ground level, all detached houses facing the lines were selected for the survey because of the simplicity of noise exposure estimates. There was no passenger train during night time from 1 to 5 A.M. though there were some freight trains. In both surveys general annoyance and activity interferences were measured with a 5-point verbal scale constructed by ICBEN Team 6: not at all, slightly, moderately, very and extremely [6]. Table 1 shows the outline of the two surveys. Table 1 Outline of social surveys Noise source railway Survey area Areas along Sanyo Line in Fukuoka Areas along four JR lines in Fukuoka Survey date April 2003 May -June 2002 Noise measurement July 2003 October 2002 Number of respondents Response rate [%] Number of trains per day L Aeq,24h [db] Noise measurements After the social survey on community response to noise, noise measurements were made. noise levels were recorded at least five times for each train type and for both near and far tracks at the reference point close to the line and points 5, 10, 20, 40 and 80 m apart from the reference point simultaneously with integral sound level meters. L AE values were calculated from noise level data recorded every 100 ms within 10 db from the maximum noise levels of noise events. Distance reduction equations, logarithmic regression equations between distance and noise reduction, were formulated separately for near and far tracks based on the L AE values. Noise exposure to each house was obtained from L Aeq,24h at the reference point and the noise reduction calculated by the formula. Since the noise barriers were constructed along the railway except in cutting areas, the noise levels were rather low: L Aeq,24h was from 32 to 50 db and L Asmax was from 51 to 73 db Almost the same measurements were made after the social survey on conventional railway noise except that the noise levels were measured about 20 times for each train type from reference points up to the 40 m point. 2.3 Vibration measurements In comparing the dose response relationships between and conventional the differences in certain responses are suggested to be attributable to the vibration from both sources as is discussed later. Thus the vibration levels from and conventional were measured in three directions at points 12.5, 25, 50, 75, 100 and 150 m from the center of the railway with vibration meters 1838

3 (RION VM-52A and VM -53A). The averaged maximum vibration level among the upper 10 events in a vertical direction (L vmax ) was used in the following analysis [7]. The measurements of vibration from the were made at five sites along the line and those from conventional were made at six sites. The distance reduction equations were formulated based on the measured values following noise reduction equations and the vibration exposure to each house was estimated. Only the response data in the areas where the vibration measurements were made were analyzed hereafter. As a result, 358 responses from noise survey and 422 from conventional railway noise survey were used in the following. 3 Results 3.1 Comparison of dose-response relationships between and conventional highly annoyed highly annoyed (a) Telephone disturbance L Aeq n.s. (c) General noise annoyance L Aeq highly annoyed highly annoyed Figure 2 compares dose-response relationships for listening disturbance, sleep interference, general noise annoyance and vibration annoyance between and conventional. There is no significant difference in the relationships for listening and sleep interferences between both noise sources. However, there is significant difference in the relationships for general noise annoyance and vibration annoyance at 1% between the sources. Such a trend for general noise annoyance is consistent with Tamura s [3]. 3.2 Comparison of noise-vibration exposure relationships between and conventional Figure 3 compares the relationships of noise and vibration exposures between and conventional. Each plotted point shows the estimated noise and vibration exposure. The linear regression lines were drawn for both sources. Though the points spread widely, the difference between both (b) Awakening n.s. L Aeq (d) Vibration annoyance L Aeq Figure 2 Comparison of dose-response relationships between and conventional 1839

4 L vmax (db) Forum Acusticum 2005 Budapest lines is significant at the 1% level. This means that vibration exposure in areas along is 5-10 db higher on average than conventional even at the same noise exposure, although the noise exposure from the was very limited. While noise and vibration exposures from the New Sanyo Line were from 32 to 50 db and 20 to 60 db, respectively, those within 100 m of the New Tokaido Line were from 29 to 63 db and from 37 to 76 db [4], respectively. The noise and vibration exposures from the New Sanyo Line were much lower than those from the New Tokaido Line probably because mo re efficient noise and vibration counter-measures were constructed for New Sanyo Line. Figure 4 compares the vibration exposure-annoyance relationships between and the conventional. There is a significant difference at the 1% level in the relationships between the vibration sources. 4 Discussion Figures 2 (a) and (b) show that people experience as much listening disturbance and sleep interference from the as from conventional. However, people were more annoyed by noise and vibration from the than from conventional. Even when the vibration level was taken as the independent variable, the vibration annoyance for was still greater than conventional as shown in Figure 4. It is generally accepted that more severe attitudes to the causes higher annoyance than conventional railway as Tamura [3] pointed out. However, the authors hypothesize that more objective reasons must exist for the significant difference in Figure 2 (c). L Aeq Figure 3 Comparison of the relation of noise to vibration exposures between and conventional % highly annoyed The present results suggest synergetic effects of vibration on noise annoyance and also noise on vibration annoyance considering Figures 2, 3 and 4, although these may not constitute definitive evidence of the cause. These results confirm the finding obtained by Sato [5] that road traffic and railway noise annoyance was higher in areas with more vibration exposure even at the same noise exposure. The synergetic effects of vibration on noise annoyance may explain the difference in railway bonus between Europe and Japan. In Euro-American surveys it has been frequently shown that railway noise is less annoying than road traffic noise [8]. However, recent Japanese studies have not shown the railway bonus [9, 10]. Morihara et al. [11] suggested that the distance from the sources to houses was the moderator to explain the difference in railway bonus between Europe and Japan. That is, houses in Japan were closer to roads and than houses in Europe. Thus the houses in Japan along are apt to be affected by vibration from trains because of more speed and weight than road vehicles. Whereas the above discussion may provide a reasonable possibility, a systematic experiment should be conducted by controlling noise and vibration levels independently in order to show clear evidence of the causal effects of vibration on noise annoyance. 5 Summary Social surveys on community response to and conventional were carried out and noise and vibration measurements were also made in Kyushu. The followings were obtained as conclusions. L vmax (db) Figure 4 Comparison of vibration exposureannoyance relationships between and conventional 1840

5 1) Annoyances caused by noise and vibration were significantly greater than those caused by conventional. This was consistent with the previous findings. 2) Vibration from the was significantly greater than that from conventional at the same noise level. 3) These strongly suggest the synergetic effects of vibration on noise annoyance. different category scales J. Sound Vib., 205, pp (1997) [11] T. Morihara et al., Comparison of dose-response relationships between railway and road traffic noises: the moderating effect of distance, J. Sound Vib., 277, pp (2004) The present study was financially supported by Grantin-Aid for Scientific Research (No ). References [1] T. Sone et al., Effetcts of High Speed Train Noise on the Community aling a Railway. J. Acoust. Soc. Jpn., Vol. 29, No. 4, pp (1973) (in Japanese) [2] Y. Machida, Study on the Sence Survey on Super-express Line Noises, Technical Report of Noise Committee, A. S. J., N (1989) (in Japanese) [3] A. Tamura, Community Response to Outdoor Noise at the Sites Exposed to or suburban Railway Noise, Technical Report of Noise Committee, A. S. J., N (1989) (in Japanese) [4] S. Yokoshima et al., A Study on Factors Constituting Annoyance Due to Railway Vibration, J. Archit. Plann. Environ., AIJ, No. 526, pp.1-7, (1999) (in Japanese) [5] Tetsumi Sato, Two surveys on the effect of vibration on traffic noise annoyance, Proceedings of Inter-noise 90, pp (1990) [6] J.M. Fields et al., Standardized General-Purpose Noise Reaction Questions for Community Noise Survey: Research and a Recommendation, J. Sound Vib., 242, pp (2001) [7] JIS C 1510: Vibration meter [8] H.M.E. Miedema et al., Exposure-response Relationships for Transportation Noise J. Acoust. Soc. Am., 104, pp (1998) [9] J. Kaku et al., The possibility of a bonus for evaluating railway noise in Japan J. Sound Vib., 193, pp (1996) [10] T. Yano et al., Comparison of community annoyance from railway noise evaluated by 1841