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From page 92... ... TCRP D-12 Final Report 89 6. ANALYSES OF QUESTIONNAIRE RESPONSES A primary goal of this study was to develop a dosage-response curve, or curves, to relate the annoyance of people living near rail transit lines to ground-borne vibration and noise that is generated by rail operations. Read the entire page →
From page 93... ... TCRP D-12 Final Report 90 ineligible because of language difficulties, or because the telephone number was a fax machine or business. The interview completion rate varied from a high of 91% (in Dallas) Read the entire page →
From page 94... ... TCRP D-12 Final Report 91 Notice/annoyance of rumbling, rattling, shaking and vibration Questionnaire items 6, 7 and 8 inquired whether respondents noticed low rumbling sounds, rattling sounds, and shaking and vibrations in their homes when trains passed by. About a third (32.2%) Read the entire page →
From page 95... ... TCRP D-12 Final Report 92 Floor of residence (Item 11 at subway sites, 12/13 in Dallas/Sacramento) A third of the respondents lived either in a single story home or in a below-grade apartment. Read the entire page →
From page 96... ... TCRP D-12 Final Report 93 Table 18: Number of Survey Respondents Reporting Annoyance System All Respondents Respondents within 37 m of Alignment Total None Any or Higher Moderate or Higher Highly Annoyed Total None Any or Higher Moderate or Higher Highly Annoyed Annoyance from Rattle Toronto 582 506 76 53 33 163 112 51 36 21 New York 281 258 23 11 3 99 84 15 8 1 Boston 304 291 13 8 5 38 31 7 3 1 Dallas 103 97 6 4 2 29 26 3 2 1 Sacramento 36 32 4 3 3 16 14 2 2 2 Total 1306 1184 122 79 46 345 267 78 51 26 Annoyance from Perceptible Vibration Toronto 582 498 84 56 28 163 111 52 36 19 New York 281 256 25 13 3 99 80 19 10 2 Boston 304 294 10 7 5 38 32 6 3 1 Dallas 103 99 4 3 2 29 26 3 2 1 Sacramento 36 28 8 5 4 16 10 6 4 3 Total 1306 1175 131 84 42 345 259 86 55 26 Annoyance from Rumble Toronto 582 445 137 63 30 163 92 71 34 18 New York 281 185 96 16 6 99 38 61 9 4 Boston 304 281 23 13 7 38 30 8 5 3 Dallas 103 83 20 5 3 29 21 8 2 2 Sacramento 36 23 13 5 5 16 9 7 4 4 Total 1306 1017 289 102 51 345 190 155 54 31 Composite (maximum of annoyance rating for rattle, perceptible vibration and rumble) Toronto 582 431 151 77 43 163 84 79 43 25 New York 281 183 98 21 7 99 36 63 14 4 Boston 304 276 28 16 9 38 25 13 6 3 Dallas 103 81 22 5 3 29 20 9 2 2 Sacramento 36 21 15 6 5 16 7 9 5 4 Total 1306 992 314 125 67 345 172 173 70 38 Table 19: Number of Respondents Reporting being Awakened in Previous Year System All Respondents Respondents within 37 m of Alignment Total No Yes Total No Yes Toronto 582 532 50 163 128 35 New York 281 267 14 99 89 10 Boston 304 291 13 38 35 3 Dallas 103 99 4 29 28 1 Sacramento 36 31 5 16 13 3 Total 1306 1220 86 345 293 52 Read the entire page →
From page 97... ... TCRP D-12 Final Report 94 Figure 47: Percentages of Respondents Reporting Annoyance Figure 48 through Figure 55 present a graphical summary of the approximate respondent locations at each transit system, along with those residents who reported being highly annoyed. Respondents were classified as "highly annoyed" if they described themselves as "very," or "extremely" annoyed by train-related vibration, low-frequency rumble, or rattle. Read the entire page →
From page 98... ... TCRP D-12 Final Report 95 Figure 49 and Figure 50 show the locations of highly annoyed residents near the Sacramento Gold and Blue lines, respectively. It is interesting to note that next to the one Gold Line resident who was highly annoyed, was a neighbor who was not annoyed. Read the entire page →
From page 99... ... TCRP D-12 Final Report 96 Figure 49: Sacramento Gold Line Respondents Reporting High Annoyance Figure 50: Sacramento Blue Line Respondents Reporting High Annoyance Read the entire page →
From page 100... ... TCRP D-12 Final Report 97 Figure 51: Dallas Blue Line Respondents Reporting High Annoyance Figure 52: Dallas Red Line Respondents Reporting High Annoyance Read the entire page →
From page 101... ... TCRP D-12 Final Report 98 Figure 53: Toronto Respondents Reporting High Annoyance Figure 54: Boston Back Bay Respondents Reporting High Annoyance Read the entire page →
From page 102... ... TCRP D-12 Final Report 99 Figure 55: Boston Blue Line Respondents Reporting High Annoyance 6.3 Relationship between Vibration Levels and Questionnaire Response Items Cumulative histograms were prepared in 3 dB-wide intervals for the questionnaire items concerning 1) notice of rail-induced rumble, rattle, or vibration, 2) Read the entire page →
From page 103... ... TCRP D-12 Final Report 100 Altogether, 24% of all respondents were at least slightly annoyed by low rumbling sounds, rattling sounds or vibrations (or by more than one of these) produced by passing trains; 9.6% were moderately or more annoyed; and only 5.1% of respondents were highly ("very" or "extremely" annoyed) Read the entire page →
From page 104... ... TCRP D-12 Final Report 101 Figure 57: Vibration Levels for 314 Respondents Annoyed to Any Degree by Train Passbys Figure 58: Vibration Levels for 125 Respondents Moderately or More Greatly Annoyed by Train Passbys 40.0 50.0 60.0 70.0 80.0 Unweighted Mean Vibration Velocity Level, dB 0% 25% 50% 75% 100% C u m u la ti v e P e rc e n t 0.0 20.0 40.0 60.0 A-weighted Mean Vibration Velocity Level, 3 dB 0% 25% 50% 75% 100% C u m u la ti v e P e rc e n t 40.0 50.0 60.0 70.0 80.0 Unweighted Mean Vibration Velocity Level, dB 0% 25% 50% 75% 100% C u m u la ti v e P e rc e n t 0.0 20.0 40.0 60.0 A-weighted Mean Vibration Velocity Level, 3 dB 0% 25% 50% 75% 100% C u m u la ti v e P e rc e n t Read the entire page →
From page 105... ... TCRP D-12 Final Report 102 Figure 59: Vibration Levels for 67 Respondents Highly Annoyed by Train Passbys Figure 60: Vibration Levels for 86 Respondents Awakened by Train Passbys 40.0 50.0 60.0 70.0 80.0 Unweighted Mean Vibration Velocity Level, dB 0% 25% 50% 75% 100% C u m u la ti v e P e rc e n t 0.0 20.0 40.0 60.0 A-weighted Mean Vibration Velocity Level, 3 dB 0% 25% 50% 75% 100% C u m u la ti v e P e rc e n t 40.0 50.0 60.0 70.0 80.0 Unweighted Mean Vibration Velocity Level, dB 0% 25% 50% 75% 100% C u m u la ti v e P e rc e n t 0.0 20.0 40.0 60.0 A-weighted Mean Vibration Velocity Level, 3 dB 0% 25% 50% 75% 100% C u m u la ti v e P e rc e n t Read the entire page →
From page 106... ... TCRP D-12 Final Report 103 Figure 61: Vibration Levels for 42 Respondents who had Complained about Train Passbys 6.4 Estimating Vibration Levels in the Homes of Varying Percentages of Respondents Affected by Rail Vibration The Gaussian distributions fitted to the histograms plotted in Figure 56 to Figure 61 can be used to estimate vibration velocity levels in homes of various percentages of respondents in the current sample who reported various effects of train passbys. Table 20 shows the means and standard deviations of these fitted distributions of un-weighted and A-weighted vibration velocity levels. Read the entire page →
From page 107... ... TCRP D-12 Final Report 104 Table 21: Equations for Estimating Percentages of the Current Sample Reporting Various Effects of Train Passbys Unweighted Leq, dB A-weighted Leq, dB Notice 64.2 + 7.7 Z% 34.9 + 10.0Z% Annoyance Slightly 65.1 + 7.4 Z% 35.6 + 9.8 Z% Moderately, very or extremely 65.6 + 7.4 Z% 36.6 + 10.2 Z% Very or extremely 65.3 + 7.5 Z% 36.8 + 10.3 Z% Awakening 65.2 + 8.4 Z% 35.9 + 12.3 Z% Complaint 66.6 + 7.4 Z% 37.1 + 11.2 Z% Table 22: Z-scores Corresponding to Cumulative Percentages of Cases (areas under the Gaussian distribution up to the tabled percentage) % of cases Z score 10% -1.28 20% -0.84 30% -0.52 40% -0.25 50% 0.00 60% 0.25 70% 0.52 80% 0.84 90% 1.28 For example, the calculation that estimates the un-weighted vibration velocity level in the homes of 10% of those respondents who noticed train passbys is: 64.2 VdB + 7.7* Read the entire page →
From page 108... ... TCRP D-12 Final Report 105 correlated offers the best chance to find a particular dosage metric that explains the largest proportion of the variance in the response variable. Table 23 summarizes the nine primary metrics that were used to develop dosage-response relationships. Read the entire page →
From page 109... ... TCRP D-12 Final Report 106 Table 24: Logistic Regression Coefficients to Predict Probability of Notice Metric (units) Logistic Regression Coefficients Variance Accounted For A B D (m) Read the entire page →
From page 110... ... TCRP D-12 Final Report 107 The logistic regression model predicting notice of trains from un-weighted mean vibration velocity levels (Leq based on 3 dB down points) in respondents' homes was statistically significant (χ21 = 226.5) Read the entire page →
From page 111... ... TCRP D-12 Final Report 108 6.6 Predicting Moderate or Greater Annoyance with Train Passbys The survey questions associated with annoyance due to a train passby were as follows: • Item 6A: "Would you say that you have been slightly annoyed, moderately annoyed, very annoyed, or extremely annoyed by low rumbling sounds inside your home as …trains pass by"? Read the entire page →
From page 112... ... TCRP D-12 Final Report 109 Table 25: Logistic Regression Coefficients to Predict Probability of High Annoyance and Moderate or Greater Annoyance Metric Logistic Regression Coefficients Highly Annoyed Moderate + Highly Annoyed A B % Variance Accounted For A B %Variance Accounted For LeqF (VdB) Read the entire page →

From page 92...

... TCRP D-12 Final Report 89 6. ANALYSES OF QUESTIONNAIRE RESPONSES A primary goal of this study was to develop a dosage-response curve, or curves, to relate the annoyance of people living near rail transit lines to ground-borne vibration and noise that is generated by rail operations.