Effect of vibration sense by frequency characteristics of impact vibration for residential floor

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1 Architectural Institute of Japan Translated Paper Effect of vibration sense by frequency characteristics of impact vibration for residential floor Ryuta Tomita and Katsuo Inoue Department of Architecture, College of Science and Technology, Nihon University, Chiyoda-ku, Tokyo, Japan Correspondence Ryuta Tomita, Department of Architecture, College of Science and Technology, Nihon University, Chiyoda-ku, Tokyo, Japan. Funding information JSPS KAKENHI (Grant Number: JP67) The Japanese version of this paper was published in Volume 79 Number 7, pages 97-9, /aije of Journal of Environmental Engineering (Transactions of AIJ). The authors have obtained permission for secondary publication of the English version in another journal from the Editor of Journal of Environmental Engineering (Transactions of AIJ). This paper is based on the translation of the Japanese version with some slight modifications. Abstract In this research, we examined the effects that the frequency characteristics of impact vibration in a residential floor have on the vibration sense of humans. We obtained the following results: (i) a frequency of Hz or more affects the vibration sense of humans; (ii) the influence of the broadband waveform on the vibration sense of humans is larger than that of the narrowband waveform; and (iii) for the broadband waveform but not for the narrowband, even a small vibration of approximately - db is perceptible. Keywords floor vibration, frequency, impact vibration, residential floor, the rubber ball vibration sense Received March 6, 8; Accepted April, 8 doi:./ Introduction Factors such as increasing population density and longer floor spans are worsening the environmental vibrations in buildings. Presently, the Guidelines for the evaluation of habitability to building vibration from the Architectural Institute of Japan are often used to evaluate the vibration of residential floors. Under I. Vertical vibration caused by human movement/equipment, it states that the / octave band analytical results obtained from the floor response waveform are compared to the performance evaluation curve shown in Figure. It also states that the floor response waveform should be obtained under the vibration assumed to be a typical vibration source in daily lives while using floors. There is no stipulation of the source or method of impact. An evaluation made using this method is influenced not only by the insulation performance (resistance) of a floor against vibration but also by changes in the impact input to the floor; therefore, for human movements, the evaluation would include changes and variations such as the type of movements and individual differences. The objective of this study was to evaluate the insulation performance (construction performance) of buildings against vibration by using criteria that have not been introduced in the field of environmental vibration. This study focused the impact vibration on floors in the vertical direction, assuming human movements. To obtain the insulation performance of a floor, as stated in the objective of this study, the impact input should be set at a constant value. Alternatively, by obtaining both input and output, resistance can be expressed as impedance or dynamic mass. To make the impact input constant, we conducted a test that uses a standard heavy/soft impact source (a rubber ball) with impact force characteristics () per JIS A 8-:. The rubber ball is widely used as a standard heavy/soft impact source to examine floor impact sound per JIS A 8-:. Its impact force characteristics include large low-frequency components and constant frequency characteristics up to Hz, which are especially suitable for impact vibrations such as human movements. In a previous paper, we confirmed that its reproducibility is stable in the frequency range -8 Hz for vertical environmental vibration. To evaluate the vibration insulation performance of a residential floor, first, the physical quantities for evaluation that correspond well to human vibration sense need to be examined. Thus, as the basic examination in this study, we focused on the frequency characteristics obtained from the vibration response waveform of a floor during an impact. We examined the effects of a range of frequencies, including frequencies other than the decision frequency (defined here as the This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. 8 The Authors. Japan Architectural Review published by John Wiley & Sons Australia, Ltd on behalf of Architectural Institute of Japan. Jpn Archit Rev July 8 vol. no. 96 6

2 wileyonlinelibrary.com/journal/jar TOMITA and INOUE frequency that determines the evaluation values when using the tangent method), on vibration sense. Among the existing studies related to this research, few have evaluated the insulation performance of a residential floor against impact by applying a constant impact. This idea is used as a foundation when examining the floor impact sound in building acoustics. For heavy floor impact sound, the measurement and evaluation methods are stipulated by JIS A 8-: and JIS A 9-:. By contrast, studies on the human sense of vibration in the vertical direction have been conducted in a wide range of areas for a long time, including a series of studies by Miwa et al. -9 Miwa et al.,6 reveal perceptual threshold and equal sensation contours for sinusoidal vibrations at sitting, standing, and lying postures. Miwa et al. proposed using the vibration greatness level to evaluate both sinusoidal and random vibration, with steady-state vibration as the subject. 7,8 In another paper, 9 they proposed another evaluation method for impact vibration. These studies present useful evaluation methods for vibration sense, although not in the field of architecture, and have been used in many studies and standards. Matsumoto and Kunimatsu summarized the perceptual threshold of continuous sinusoidal vibration according to studies in various fields, both domestic and international, including a paper by Miwa and Yonekawa, 7 and they presented a frequency dependence of the mean perceptual threshold. This is a useful attempt and reference for the threshold of human vibration sense. However, the studies by Miwa and Yonekawa 7 and Matsumoto and Kunimatsu are based on results using sinusoidal vibration, whereas one of the methods proposed by Miwa and Yonekawa 9 is only used when the base frequency does not change much. Another study by Miwa and Yonekawa, 8 in contrast, uses steady-state vibration as the subject. Floor vibration caused by human movement, as in this study, obviously has complex time and frequency characteristics, and the response varies with the decay of the floor. Thus, these methods cannot be applied without modification. In the field of architecture, Ishikawa and Noda set up a room on a shake table, and based on the results of a human subject experiment with steady-state vertical sinusoidal vibration, they presented perception and response probabilities in the sensory evaluation. Yokoyama and Ono, conducted studies on the floor vibration generated by human movements and presented VI() as a physical quantity that represents the sensory hierarchy of humans. They compared it with an evaluation index of floor vibration and proposed a method for evaluating floor vibration that can be applied for a floor with a natural frequency in the range of - Hz. In addition, Yokoyama et al. recreated response waves simulating the floor vibration that is generated by walking on a shake table, in addition to a sine wave, and proposed a physical quantity that corresponds well to the evaluation of periodic or continuous vibration. They examined a vibration waveform with dominant frequency components in the range of -6 Hz. Takahashi et al., using pedestrian bridges and long span floors with a natural frequency of Hz or lower, showed that the converted acceleration obtained from the mean of the maximum vibration levels and the level of perception correspond to each other well. Takahashi et al. obtained sensorily equivalent vibrations for 6 types of vibration with different standard sine waves, natural frequencies, and attenuation constants (natural frequencies of,,, and Hz) on a shake table and showed that the vibration level and converted acceleration are both effective. Thus, they achieved useful results for each objective. Parts of studies that focused specifically on the floor Figure. The curve of performance evaluation for vertical vibration vibration generated by human movements - are useful for the present study, but these studies are the results of vibration with a main component of Hz or less. In this study, as a fundamental method for evaluating the vibration insulation performance of a residential floor, we examined the vibration sense of humans and the floor vibration response generated in an actual floor slab. Since there are few reports on floor vibration due to human movements (random vibration and impact attenuation vibration) that exceed Hz, in this study, we experimented with a / octave band analysis up to the 8 Hz band. The experimental method did not use a shake table but applied impact on an actual floor slab and generated various random vibrations through combinations of vibration and receiving points. Although the Guidelines for the evaluation of habitability to building vibration use the tangent method for evaluation, when humans feel vibration, they perceive not only the vibration of the dominant frequency but also that of other frequencies, which influences the Sensation of the magnitude of vibration. In the waveform in the / octave band analysis, compared to a case in which only the decision frequency is dominant, when other frequency components have similar amplitudes, its influence is assumed to be large. Therefore, we conducted an experiment on the effects of the characteristics of frequencies other than the decision frequency on vibration sense.. Experimental methods The experimental methods used three floors with steel (S) construction and reinforced concrete construction, as shown in Table. Figure shows a plan view and the measurement (receiving) points for floors A, B, and C. At the vibration points shown in Figure, a rubber ball was dropped from a height of m, and the vibration response acceleration was measured at each receiving point using a vibration level meter (VM-A) to perform the / octave band analysis. At each receiving point, we performed a sensory evaluation experiment with a human subject. Subjects evaluated the vibration at the receiving points with four levels: //I feel it clearly/. Excluding the subjects who responded with, we had the other subjects evaluate the vibration with four patterns: It is not unpleasant/i can t say it either way/it is unpleasant/it is quite unpleasant. Jpn Archit Rev July 8 vol. no. 97

3 TOMITA and INOUE wileyonlinelibrary.com/journal/jar Table. Overview of the floor structure Construction Floor construction (unit: mm) Slab dimensions (unit: m) Primary natural frequency and attenuation rate, h A-floor Steel construction Deck PL-.+ ordinary concrete 8+ mortar + PVC sheet B-floor C-floor Reinforced concrete construction Reinforced concrete construction 9 Hz,.% Ordinary concrete + mortar. 9.6 Hz,.% + P tile mm Ordinary concrete + mortar 9 6 Hz,.% Figure. The curve of performance evaluation for vertical vibration. Numbers in Figure correspond to Figures, and and Figures 9, and The perception rate in this paper was calculated for each receiving point by dividing the number of + I feel it strongly votes by the total number of votes and multiplying by (%). The perception level and level of discomfort were scaled using the method of successive categories. To exclude the audiovisual effects of the rubber ball falling, subjects wore ear plugs and faced away from the vibration points so they could not see the rubber ball falling. Subjects sat directly on the floor, holding their knees. In a preliminary experiment, we confirmed that the impact noise of the rubber Jpn Archit Rev July 8 vol. no. 98

4 wileyonlinelibrary.com/journal/jar TOMITA and INOUE ball did not affect the vibration evaluation. During the experiment, desks and chairs were moved so there was nothing on the floor within the experimental target range. The subjects consisted of adults. Seven subjects evaluated receiving points twice for the A-floor. Thirteen subjects evaluated receiving points times for the B-floor. Ten subjects evaluated receiving points times for the C-floor. Therefore, the total number of votes for the sensory evaluation experiments was.. Effects of frequencies between Hz and 8 Hz on vibration sense. Examination of perception degree and acceleration response waveform for each point Figures - show some analytical results for the / octave band concerning the perception degree and response acceleration waveform for each floor. The sensory evaluation results in Figure show that the ratio of increases on the order of??. The response acceleration is < when evaluated with the tangent method up to Hz, which is the evaluation range of the Guidelines for the evaluation of habitability to building vibration, and does not correspond well to the sensory evaluation results. Therefore, we extended the performance evaluation curve to 8 Hz with a slope of +6 db/octave (oct.). In and, Hz became the decision frequency, and the correspondence was better, on the order of <<. The sensory evaluation results in Figure show similar perception degrees. The response acceleration in is much smaller than that in at a frequency of Hz or lower, but when considering a frequency range of. Hz and higher, Hz becomes the decision frequency, and the evaluation of the response acceleration is similar. The sensory evaluation results in Figure show that vibration with a frequency of. Hz and higher clearly affects perception. These vibrations peak at Hz and correspond well on the order of 6<7<8 in the response acceleration and sensory evaluations. As such, when the sensory evaluation experiment was conducted with subjects in a real building, frequency components of Hz or higher had strong effects on vibration sense. However, further verification is necessary to determine whether perception at Hz or higher can be evaluated at +6 db/oct.. Examination of sensory evaluation and physical quantities for evaluation Figure 6 shows the correspondence of VRAL and the rate of perception. VRAL is a value obtained in the following manner: based on the performance evaluation curve (we used +6 db/ oct. for. Hz and higher) for vertical vibration in Figure, the vibration response acceleration at the decision frequency is moved horizontally along the evaluation curve, and the value for the part with a constant acceleration for -8 Hz (a <m/ s >) is obtained; VRAL is then calculated as 9 log(a / ) <db>. In other words, VRAL evaluates the acceleration of the most dominant frequency in the vibration evaluation curve in Figure, which considers the human sense of vertical vibration. () in Figure 6 indicates the relationship between the rate of perception and VRAL V.-, as obtained from the vibration response acceleration in the decision frequency range from. to Hz, which is the evaluation range in the Guidelines for the evaluation of habitability to building vibration. It shows that, as discussed above, a frequency component of. Hz and higher has effects and that there is no correlation. On the other hand, when evaluated between. and 8 Hz, as shown in curve () in Figure 6, subjects began to perceive vibration starting at VRAL V.-8 = 6 db, and as VRAL increased, the perception rate increased. At approximately 7 db, 9% of the subjects perceived vibration. Figure in the Guidelines for the evaluation of habitability to building vibration shows that with a V- (ie, the level at which % of the subjects perceive vibration) of 8 db and a V-9 of 7 db, these values are mostly consistent with the experimental results given in curve () in Figure 6. Because the current Guidelines for the evaluation of habitability to building vibration only target Hz or lower, as in curve () in Figure 6, it is necessary to extend the frequency range to Hz and higher based on the present experimental results. Figures 7 and 8 show the results obtained for VRAL, perception degree, and discomfort degree. Figure 7 () shows that, similar to the perception rate in Figure 6, the perception degree and VRAL, as calculated from the response acceleration at Hz and lower, do not correspond well and have no relationship. However, as in Figure 7 (), when the horizontal axis is the VRAL that considers response acceleration up to 8 Hz, the evaluation becomes at Figure. Example of sense evaluation and frequency characteristics (A-floor) Jpn Archit Rev July 8 vol. no. 99

5 TOMITA and INOUE wileyonlinelibrary.com/journal/jar Figure. Example of sense evaluation and frequency characteristics (B-floor) Figure. Example of sense evaluation and frequency characteristics (C-floor) % 8% and rate of percep on % 8% y =.8x.98 R² =.6 6% 6% % % % % % % Figure 6. Corresponding rate of perception and VRAL Jpn Archit Rev July 8 vol. no.

6 wileyonlinelibrary.com/journal/jar TOMITA and INOUE I feel it strongly I feel it strongly y =.8x.9 R² =.679 I feel it slightly I feel it slightly Figure 7. Corresponding perception degree and VRAL It is quite It is I can t say it either way It is quite It is I can t say it either way y =.96x.97 R² =.6 It is not It is not Figure 8. Corresponding discomfort degree and VRAL VRAL = 6 db and at 7 db, showing good correspondence to the regression line. Figure 8 () shows that, similar to the perception rate and perception degree, VRAL, as calculated with the response acceleration at Hz and lower, and the discomfort degree do not correspond well. In contrast, when the horizontal axis is the VRAL that considers response acceleration up to 8 Hz and when examining the regression line for data at 6 db and higher, as the value exceeded VRAL = 66 db, the evaluation became a range of I can t say it either way to it is. This shows good correspondence to the regression line. Thus, by considering frequency components of Hz and higher for perception degree and discomfort degree, the physical quantities for evaluation and sensory quantity correspond well; thus, frequency components of Hz and higher need to be considered.. Effects of frequencies other than the decision frequency on vibration sense. Examination of perception degree and acceleration response waveform Figures 9- show the analytical results of the perception degree and response acceleration waveform for each floor. Based on the results discussed in Section, we examined the evaluation frequency range up to 8 Hz. Figures 9- show that the evaluation of the response acceleration at the decision frequency in Figure of the Guidelines for the evaluation of habitability to building vibration was approximately V-8; however, Figures 9- show frequency characteristics with greater contributions in the broadband, and the sensory evaluation result has a higher perception degree. Figures - show that although the Hz band has a similar amplitude, Figures - have more 6-6 Hz band components and a higher perception degree. Furthermore, although Figures -6 show similar response accelerations at the 6,, and Hz bands, in the other frequency bands, Figures - present higher response accelerations. These are frequency characteristics with a large contribution across the broadband. Similarly, the perception degree is higher in Figures -. As shown in these examples, when the vibration has a high response acceleration for broadband and has mountain-shaped frequency characteristics, compared to cases in which only the decision frequency is dominant, both the perception rate and perception degree tend to be high. Therefore, when evaluating vibration that includes broadband components, not only the vibration response acceleration at the decision frequency but also other frequency bands should be considered to obtain a better correspondence to vibration sense.. Examination of sensory evaluation and physical quantities for evaluation Here, we examined the effects of the frequency components other than the decision frequency on vibration sense for the VRAL (.-8 Hz) obtained from the response acceleration. Figure separates the correspondence of VRAL and perception rate for the narrowband (assuming that the VRAL of the decision frequency is db higher than the VRAL of the other frequencies) and the broadband ( db or below). Figure () Jpn Archit Rev July 8 vol. no.

7 TOMITA and INOUE wileyonlinelibrary.com/journal/jar Figure 9. Example of sense evaluation and frequency characteristics (B-floor, ) Figure. Example of sense evaluation and frequency characteristics (B-floor, ) indicates the VRAL for the decision frequency and perception rate, and Figure () shows the relationship between the synthetic VRAL, where bands within db are synthesized energy and perception rate. When a regression line is drawn for VRAL V.-8 = 6 db, where subjects begin to perceive vibration as in Figure 6 (), the evaluation method that synthesizes the VRAL of frequencies other than the decision frequency for broadband, as in Figure (), can evaluate without differentiating between the narrowband and the broadband. In this study, we examined values to differentiate the narrowband and the broadband using several patterns and used db, which provided good correspondence. However, due to the spectrum shape, the effect on vibration sense is expected to change. Thus, this point needs further examination. The correspondence of the VRAL for the decision frequency and perception degree in Figure () shows that, similar to the perception rate, the perception degree in the broadband is larger than that in the narrowband at the same VRAL value. The regression line for data at 6 db or higher shows that there is a -db difference in the evaluation of I feel it clearly. By including frequencies other than the decision frequency in Figure (), VRAL, as synthesized for frequencies within db of the decision frequency, and perception degree show good correspondence, with a small difference of approximately db in the evaluation of. The correspondence of VRAL and discomfort degree for the decision frequency in Figure () shows that, unlike the perception rate and perception degree, there is little difference between the narrowband and the broadband. Since the data used in this study are from a single vibration, the vibration was not very, unlike an experimental condition. In other words, the evaluation criteria are different for unpleasantness compared to sense. Discomfort degree is fundamentally dependent on time and frequency characteristics, and examinations that consider time characteristics are needed in the future. For a relatively large vibration in Figure (VRAL db), discomfort degree was distributed from I can t say either way to it is, but the VRAL of the Jpn Archit Rev July 8 vol. no.

8 wileyonlinelibrary.com/journal/jar TOMITA and INOUE Figure. Example of sense evaluation and frequency characteristics (B-floor, 6) ()VRAL V.-8 and perception rate ()Synthesized VRAL V.-8 (synthesized from the maximum to within db) and perception rate % 8% 6% y =.96x.68 R² =.69(broadband) % 8% 6% y =.x.86 R² =.87(narrowband) % % y =.x.86 R² =.87(narrowband) % % y =.x.6 R² =.76(broadband) % % VRAL V.-8 (Addi on) (db) Figure. Corresponding rate of perception and VRAL by addition within db ()VRAL V.-8 and perception degree y =.x.88 R² =.6(broadband) ()Synthesized VRAL V.-8 (synthesized from the maximum value to within db) and perception degree y =.x 6.6 R² =.8(narrowband) I do not feel it y =.x 6.6 R² =.8(narrowband) I do not feel it y =.x R² =.78(broadband) Figure. Corresponding perception degree and VRAL by addition within db decision frequency in Figure () had a higher discomfort degree in the broadband. The VRAL (synesthetic) in Figure (), however, had a similar distribution of discomfort degree. Therefore, similar to the perception degree, VRAL (synthetic) had better correspondence with the discomfort level. However, the discomfort degree and level of concern are fundamentally affected by exposure time; thus, re-examination with data that are not from a single vibration is necessary. As such, compared to vibration in which only the decision frequency is dominant in the narrowband components, vibration that contains the broadband components has a better correspondence to the vibration sense if the evaluations account Jpn Archit Rev July 8 vol. no.

9 TOMITA and INOUE wileyonlinelibrary.com/journal/jar It is quite It is ()VRAL V.-8 and discomfort degree y =.x. R² =.68(broadband) I can t say it either way It is not y =.9x.8 R² =.679(narrowband) ()Synthesized VRAL V.-8 (synthesized from the maximum value to within db) and discomfort degree It is quite It is I can t say it either way y =.9x.8 R² =.679(narrowband) It is not y =.x 6. R² =.7(broadband) Figure. Corresponding discomfort degree and VRAL by addition within db for frequency components other than the decision frequency. However, further examination of the synthesis method for each frequency band component is necessary.. Effects of the number of bands on vibration sense The results discussed in Section show that in contrast to a waveform of narrowband components, a waveform that contains broadband components led subjects to perceive the vibration more strongly. Therefore, because the effects of the range of natural frequencies of the floor, the amount of resonance amplification in natural frequencies, and the degree of higher order resonance must all be considered, it is important to understand the frequency characteristics and perform a comprehensive evaluation. However, as we discussed before, the Guidelines for the evaluation of habitability to building vibration do not consider frequency components other than the decision frequency. Thus, in this study, we referred to the results discussed in Section and included the decision frequency, and we then focused on the / octave band number with VRAL within db. We also examined the effects of the number of bands on vibration sense. From all of the experimental data in Table, we extracted the experimental patterns of VRAL V.-8 = 6 db or higher based on the results discussed in Section and examined the number of bands and vibration sense for the data ranging from the narrowband to band number. We selected the number of bands that shows values within db for the decision frequency and the VRAL of the decision frequency. In the present experimental data, there are data points for the narrowband (band ), data points for band, data points for band, data points for band, and data points for band, for a total of data points. This report divided these data points into data points for the narrowband (band ), 9 data points for bands and, and 7 data points for bands and. Figure shows the [(perception rate obtained in a sensory evaluation experiment) (perception rate calculated by obtaining the VRAL of the decision frequency in an experiment and applying the Guidelines for the evaluation of habitability to building vibration : VRAL range is db)] for each band number. The results of an analysis of variance show that the P-value is.; thus, there is a significant difference in perception rate between the number of bands, with a significance level of %. In addition, the results of a multiple comparison test show that the population means are not equal between the narrowband (band ) and bands and, with a significance level of %, and between the narrow band (band % % % % % % % % % Mean+SD Mean+SE Mean Mean SE Mean SD Bands and Bands and Figure. Difference in perception rate due to change in the number of bands ) and bands and, with a significance level of %. In other words, bands and and bands and had 8% and % larger perception rates, respectively, than those obtained under the Guidelines for the valuation of habitability to building vibration. The mean for the narrow band (band ) was -%, which corresponds well to the Guidelines for the evaluation of habitability to building vibration. Figure 6 shows the [(the VRAL of only the decision frequency obtained in an experiment) (the VRAL calculated by obtaining perception rate in a sensory evaluation experiment and applying the Guidelines for the evaluation of habitability to building vibration : perception rate range is %- %)] for each band number. The results of the analysis of variance show that since the P-value is., there is a significant difference in VRAL between the number of bands, at a significance level of %. The results of the multiple comparison test show that population means are not equal between the narrowband (band ) and bands and or between the narrowband (band ) and bands and, with a significance level of %. The results for the narrowband (band ) show good correspondence to the Guidelines for the evaluation of habitability to building vibration, with a mean of. db, but Jpn Archit Rev July 8 vol. no.

10 wileyonlinelibrary.com/journal/jar Figure 6. bands Mean+SD Mean+SE Mean Mean SE Mean SD Bands and Bands and Difference in VRAL due to change in the number of the values are small for bands and, at.8 db, and for bands and, at.6 db. In other words, based on sense, subjects perceive vibration at a small VRAL of db in bands and and db in bands and. As such, when the dominant frequency is broadband, compared to a vibration in which only the narrowband (band ) is dominant, even a small vibration of - db may be perceived. As physical properties for evaluation, we observed the physical quantities of the synthetized VRAL (synthetic) that includes the VRAL of frequencies within db of the VRAL of the decision frequency. There is no significant difference in the division of the narrowband, bands and, and bands and, and the results are within the range of. db to +.8 db. For the method of adding band components, when there is a continuous spectrum, the perception rate of vibration often depends on changes in the spectral level. However, the present paper shows that there is a significant difference in energy with the addition of the number of bands within db. 6. Conclusions In this paper, we performed a fundamental examination of physical quantities for evaluating the insulation ability of a residential floor against vibration and vibration sense. Taking the impact vibration generated in actual floor slabs as our focus, we performed an experiment on the frequency characteristics and obtained the following results:. Examining the effects of the frequency characteristics between the. Hz and 8 Hz bands showed that based on the correspondence of vibration sense evaluation and physical quantities, frequency components of Hz and higher are perceived.. Considering frequency components of Hz and higher, for a waveform with frequency characteristics in the narrowband, subjects began to sense vibration at a VRAL of approximately 6 db, and 9% of the subjects sensed vibration at 7 db. Our results on the narrowband showed that impact vibration corresponds well to the Guidelines for the evaluation of habitability to building vibration based on sinusoidal vibration.. When components at Hz or higher are considered for perception degree and discomfort degree, the correspondence improves. However, since discomfort degree is fundamentally affected by exposure time, another examination that considers the time axis is necessary.. A waveform with a narrowband component and a waveform with a broadband component show that even if the VRAL of the decision frequency is the same, according to the sensory evaluation results, the perception rate and perception degree are clearly higher when there is a broadband component. For the discomfort degree, the difference is not as great as that between the perception rate and perception degree, but for large vibrations with 7 db and higher, the differences are higher when there is a broadband component.. For a waveform with only a narrowband component and for a waveform with broadband components, a relatively simple comparison method that adds the energy of the VRAL of the decision frequency and the energy of db and higher shows good correspondence in an attempt to examine the evaluation quantities for vibration sense. 6. If we summarize the [(perception rate obtained in a sensory evaluation experiment) (perception rate calculated with the Guidelines for the evaluation of habitability to building vibration using the VRAL obtained in an experiment for the decision frequency only)] for the decision frequency and number of bands with db and higher, compared to the narrow band (the decision frequency only, band ), the perception rate increases by 8% and % for bands and and bands and, respectively. 7. If we summarize the [(the VRAL of the decision frequency obtained in an experiment) (the VRAL calculated with the Guidelines for the evaluation of habitability to building vibration with perception rate obtained in a sensory evaluation experiment)] for a number of bands, compared to the narrowband (the decision frequency only, band ), subjects perceived small vibrations at.8 db and.6 db for bands and and bands and, respectively. In the future, we will examine the physical quantities for evaluation that correspond well with vibration sense, including the effects of exposure time to vibration, and examine a method for evaluating the insulation ability of buildings against vibrations (building performance). Acknowledgments Part of this work was supported by JSPS KAKENHI grant number JP67. We extend our sincere appreciation to Mr. Wataru Ito, a 8 Master s program student at Nihon University, who provided much support to experiment of this study. Disclosure The authors have no conflict of interest to declare. References TOMITA and INOUE Architectural Institute of Japan. Guidelines for the evaluation of habitability to building vibration,. (In Japanese) Jpn Archit Rev July 8 vol. no.

11 TOMITA and INOUE wileyonlinelibrary.com/journal/jar Tomita R, Inoue K, Ito W. Floor vibration response on various movement of persons and the rubber ball impact, AIJ Journal of Technology and Design, 7, pp 79-8, 8 (In Japanese) JIS A 8-:. Acoustics-Measurement of floor impact sound insulation of buildings-part : Method using standard heavy impact sources (In Japanese) JIS A 9-:. Acoustics-Rating of sound insulation in buildings and of building elements-part : Floor impact sound insulation (In Japanese) Miwa T. Evaluation methods for vibration effect, part. Measurements of threshold and equal sensation contours of whole body for vertical and horizontal vibrations, Industrial Health,, pp. 8-, Miwa T, Yonekawa Y. Evaluation methods for vibration effect, part 9. Response to sinusoidal vibration at lying posture, Industrial Health, 7, pp. 6-6, Miwa T, Yonekawa Y. Evaluation methods for sinusoidal vibrations- evaluation methods for vibrations, The Journal of the Acoustical Society of Japan, 7 (), pp. -, 97 (In Japanese) 8 Miwa T, Yonekawa Y. Evaluation methods for compound sinusoidal and random vibrations- evaluation methods for vibrations, The Journal of the Acoustical Society of Japan, 7 (), pp. -, 97 (In Japanese) 9 Miwa T, Yonekawa Y. Evaluation methods for pulsed vibration- evaluation methods for vibration, The Journal of the Acoustical Society of Japan, 7 (), pp. -9, 97 (In Japanese) Matsumoto Y, Kunimatsu S. Discussion on the evaluation of environmental vibration based on human vibration perception thresholds, Proceedings of the Spring Meeting of the Institute of Noise Control Engineering of Japan, pp.-, (In Japanese) Ishikawa T, Noda C. Experimental investigation on perception threshold and sensory evaluation for vertical vibration, Journal of Environmental Engineering (Transaction of AIJ), 88, pp. 9-, (In Japanese) Yokoyama Y, Ono H. Indicating methods of floor vibrations caused by human activities based on human sensations- in the case of difference the vibration cause and the perceiver, Journal of Structural and Construction Engineering (Transaction of AIJ), 9, pp. -9, 988 (In Japanese) Yokoyama Y, Ono H. Presentation of the evaluation method for floor vibration when a different person causes and perceives the vibration- study on method for evaluating vibrations of building s floors caused by human activities from a viewpoint of comfort (Part ), Journal of Structural and Construction Engineering (Transaction of AIJ), 8, pp. -8, 99 (In Japanese) Yokoyama Y, Inoue R, Ikeda A, Yagi Y. Evaluation index on periodic and continuous floor vibration caused by occupant walking, Journal of Environmental Engineering (Transaction of AIJ), 66, pp. -, 9 (In Japanese) Takahashi Y, Katayama K, Yoshioka H, Imazawa T, Murai N. Experimental study on damping effect of floor structure (Part ) - maximum amplitude and sensory evaluation of floor vibration caused by walking, Transactions of AIJ. Journal of Structural and Construction Engineering, 9, pp. 8-88, (In Japanese) How to cite this article: Tomita R, Inoue K. Effect of vibration sense by frequency characteristics of impact vibration for residential floor. Jpn Archit Rev. 8;: Jpn Archit Rev July 8 vol. no. 6