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From page 181... ... B-3 C H A P T E R B - 1 Introduction to Appendix B This appendix presents the details of the Phase 2 research data collection and analysis at three soundabsorbing, single-barrier locations. It does not provide background on the subject, data collection and analysis protocols, comparison to the Phase 1 results, overall findings, applications, recommendations, or suggested research. Read the entire page →
From page 182... ... B-4 C H A P T E R B - 2 Study Locations Measurements were made at the following three study locations during the week of November 15, 2016: 1. Read the entire page →
From page 183... ... B-5 Figure 1. General microphone placement and naming convention diagram. Read the entire page →
From page 184... ... Table 1. Studied Phase 2 locations. Read the entire page →
From page 185... ... B-7 C H A P T E R B - 3 Results – I-75, Troy, Ohio (Location OH-1) As shown in Figure 2, the I-75 location in Troy, Ohio, is a six-lane freeway. Read the entire page →
From page 186... ... B-8 Figure 2. I-75 No Barrier view (top left) Read the entire page →
From page 187... ... B-9 Figure 3. I-75 microphone positions. Read the entire page →
From page 188... ... B-10 Figure 4. I-75 BarRef01 (top left) Read the entire page →
From page 189... ... B-11 Figure 5 shows cross-sections at the Barrier and No Barrier sites. The cross-section at the No Barrier site is virtually identical to the Barrier site: the ground elevation is 0.5 ft. Read the entire page →
From page 190... ... B-12 BarCom03 and NoBarCom05 -- Figure 9 (unweighted) and Figure 10 (A-weighted) Read the entire page →
From page 191... ... B-13 Figure 7. Running Leq (5 min.) Read the entire page →
From page 192... ... B-14 Figure 9. Running Leq (5 min.) Read the entire page →
From page 193... ... B-15 Figure 11. Differences in running Leq (5 min.) Read the entire page →
From page 194... ... B-16 Figure 13. Running Leq (5 min.) Read the entire page →
From page 195... ... B-17 described in the AWP, source equivalence was determined by the NoBarRef02 A-weighted Leq (5 min.) in each period and averages of speeds in each period (for the second lane from the outside for each direction, for the overall speed by direction, and for the overall combined speed for both directions) Read the entire page →
From page 196... ... Figure 16. Equivalent 5-minute periods for Calm Inversion groups at I-75. Read the entire page →
From page 197... ... B-19 Table 4. Two-way traffic volumes in 5-minute periods, by equivalent group for Calm Inversion and Upwind Inversion conditions, sorted by factored hourly volume, I-75. Read the entire page →
From page 198... ... B-20 Figure 17. Sample sound pressure level spectra for BarRef01 and NoBarRef02, I-75, Calm Inversion group CIG-1-1, 20:03-20:08 (Leq (5 min.) Read the entire page →
From page 199... ... B-21 Figure 18. Sample sound pressure level spectra for BarCom03 and NoBarCom05, I-75, Calm Inversion group CIG-1-1, 20:03-20:08 (Leq (5 min.) Read the entire page →
From page 200... ... B-22 Figure 19. Sample sound pressure level spectra for BarCom04 and NoBarCom06, I-75, Calm Inversion CIG-1-1, 20:03-20:08 (Leq (5 min.) Read the entire page →
From page 201... ... B-23 The trends across the one-third octave band frequencies, described below, are generally similar in these individual groups of equivalent periods, with some differences likely related to background noise and the uniqueness of vehicle noise sources in each period. Figure 20 shows in the upper graph that the BarRef01 levels are roughly 0.6 dB to 2.7 dB higher than the NoBarRef02 levels across the entire spectrum, except at 20 Hz, where the difference is only 0.2 dB. Read the entire page →
From page 202... ... B-24 Figure 20. Averages of the differences in Leq (5 min.) Read the entire page →
From page 203... ... B-25 Effects of Traffic Volume and Speed While all the 5-minute periods in all the groups were not equivalent in traffic volume across all the groups, the average differences in the paired microphone levels are consistent with the results in the individual groups. As evidence of that consistency, Figure 21 and Figure 22 show the level difference graphs for, respectively, a group of higher-volume periods (CIG-27-1) Read the entire page →
From page 204... ... B-26 Figure 21. Differences in Leq (5 min.) Read the entire page →
From page 205... ... B-27 Figure 22. Differences in Leq (5 min.) Read the entire page →
From page 206... ... B-28 Upwind Inversion Class Figure 23 shows three graphs of the differences in level between comparable microphones for the single Upwind Inversion groups with their error bars. This figure compares the following: BarRef01 and NoBarRef02 in the upper graph. Read the entire page →
From page 207... ... B-29 Figure 23. Averages of the differences in L eq (5 min.) Read the entire page →
From page 208... ... B-30 Comparison of Upwind Inversion and Calm Inversion Results Figure 24 compares the differences in one-third octave band levels for the single group in the Upwind Inversion class and the averages for all the Calm Inversion groups. The data values are the Upwind Inversion differences minus the average Calm Inversion differences for each frequency band. Read the entire page →
From page 209... ... B-31 Figure 24. Differences in the Upwind Inversion average differences and the Calm Inversion average differences (Leq (5 min.) Read the entire page →
From page 210... ... B-32 Additional Sound Level Analysis for I-75 – Ln Descriptors In addition to the examination of the differences in levels for the equivalent pairs of running 5-minute Leq data, the differences in the Ln descriptors for the overall data without segregation into equivalent periods were investigated. The focus was on the possible change in the background level in the presence of the noise barrier. Read the entire page →
From page 211... ... B-33 Figure 26. Differences in broadband A-weighted 5-minute L90, L99 and Leq, I-75, BarRef01 and NoBarRef02. Read the entire page →
From page 212... ... B-34 Figure 27. Read the entire page →
From page 213... ... B-35 Figure 29. Read the entire page →
From page 214... ... B-36 BarRef01 levels are higher than the NoBarRef02 levels and blue means that NoBarRef02 is higher. In the graph, time runs from top to bottom (increasing as one moves down each figure, with each row representing the starting minute of a running 5-minute period) Read the entire page →
From page 215... ... B-37 Figure 34 presents the Ln differences for BarCom04 and NoBarCom06. Below 2 kHz, there is not strong color indication of higher levels at BarCom04, perhaps except for the 63 Hz to 100 Hz range. Read the entire page →
From page 216... ... B-38 The 5-minute data block spectrograms indicate the following trends: 1. For the barrier side of the highway reference positions, where the microphone is placed between the road and barrier at the Barrier site and at the same position for the No Barrier site, the hottest spots (dark red) Read the entire page →
From page 217... ... B-39 Figure 35. I-75 5-minute spectrograms; top: BarRef01, bottom: NoBarRef02, start time 17:55. Read the entire page →
From page 218... ... B-40 Figure 36. I-75 5-minute spectrograms; top: BarCom03, bottom: NoBarCom05, start time 17:55. Read the entire page →
From page 219... ... B-41 Figure 37. I-75 5-minute spectrograms; top: BarCom04, bottom: NoBarCom06, start time 17:55. Read the entire page →
From page 220... ... B-42 Figure 38. I-75 5-minute spectrograms; top: BarRef01, bottom: NoBarRef02, start time 19:05. Read the entire page →
From page 221... ... B-43 Figure 39. I-75 5-minute spectrograms; top: BarCom03, bottom: NoBarCom05, start time 19:05. Read the entire page →
From page 222... ... B-44 Figure 40. I-75 5-minute spectrograms; top: BarCom04, bottom: NoBarCom06, start time 19:05. Read the entire page →
From page 223... ... B-45 Figure 41. I-75 heavy truck pass-by event at ~18:18 spectrograms; top: BarCom03, bottom: NoBarCom05. Read the entire page →
From page 224... ... B-46 Figure 42. I-75 heavy truck pass-by event at ~18:18 spectrograms; top: BarCom04, bottom: NoBarCom06. Read the entire page →
From page 225... ... B-47 Figure 43. I-75 heavy truck pass-by event at ~18:33 spectrograms; top: BarCom03, bottom: NoBarCom05. Read the entire page →
From page 226... ... B-48 Figure 44. I-75 heavy truck pass-by event at ~18:33 spectrograms; top: BarCom04, bottom: NoBarCom06. Read the entire page →
From page 227... ... B-49 C H A P T E R B - 4 Results – I-70, South Vienna, Ohio (Location OH-2) As shown in Figure 45, the I-70 location in South Vienna, Ohio, is a six-lane freeway. Read the entire page →
From page 228... ... B-50 Figure 45. I-70 No Barrier view (top left) Read the entire page →
From page 229... ... B-51 Figure 46. I-70 microphone positions. Read the entire page →
From page 230... ... B-52 Figure 47. I-70 BarRef01 (top left) Read the entire page →
From page 231... ... B-53 Figure 48 shows cross-sections at the I-70 Barrier and No Barrier sites. The cross-section at the No Barrier site is like the Barrier site, with the ground elevation being a foot lower at BarRef01 compared to NoBarRef02. Read the entire page →
From page 232... ... B-54 Measured Broadband Levels and Level Differences for I-70 The running Leq (5 min.) for each site are presented in the following figures to give an overall picture of the measured levels, both in terms of unweighted sound pressure levels and A-weighted sound levels: • BarRef01 and NoBarRef02 -- Figure 49 (unweighted) Read the entire page →
From page 233... ... B-55 Figure 50. Running Leq (5 min.) Read the entire page →
From page 234... ... B-56 Figure 52. Running Leq (5 min.) Read the entire page →
From page 235... ... B-57 Figure 54. Differences in running Leq (5 min.) Read the entire page →
From page 236... ... B-58 Figure 56. Running Leq (5 min.) Read the entire page →
From page 237... ... B-59 source equivalence for I-70, the allowable variation in the NoBarRef02 Leq (5 min.) between the periods in a group was 0 dB in most cases and 0.1 dB in a few cases, and the allowable average speed differences between periods was 5 mph. Read the entire page →
From page 238... ... B-60 Figure 59. Equivalent 5-minute periods for Calm Lapse groups at I-70. Read the entire page →
From page 239... ... Figure 60. Equivalent 5-minute periods for Calm Neutral groups at I-70. Read the entire page →
From page 240... ... B-62 Table 7. Two-way traffic volumes in 5-minute periods, by equivalent group for Calm Inversion, Calm Lapse, Calm Neutral, and Downwind Lapse conditions, sorted by factored hourly volume, I-70. Read the entire page →
From page 241... ... B-63 Figure 62, Figure 63, and Figure 64 present the sound pressure level spectra for, respectively: î BarRef01/NoBarRef02. Read the entire page →
From page 242... ... B-64 Figure 63. Sample sound pressure level spectra for BarCom03 and NoBarCom05, I-70, Calm Inversion group CIG-1-1, 16:56-17:01 (Leq (5 min.) Read the entire page →
From page 243... ... B-65 Figure 64. Sample sound pressure level spectra for BarCom04 and NoBarCom06, I-70, Calm Inversion group CIG-1-1, 16:56-17:01 (Leq (5 min.) Read the entire page →
From page 244... ... B-66 10 kHz. Graphs for all the individual Calm Lapse groups are in spreadsheet files in the project record. Read the entire page →
From page 245... ... B-67 Figure 65. Averages of the differences in Leq (5 min.) Read the entire page →
From page 246... ... B-68 Calm Neutral Class Figure 66 shows the averages of the average level differences between the Barrier and No Barrier microphones' levels for all the Calm Neutral groups. Like the Calm Lapse groups, the BarRef01 levels (upper graph) Read the entire page →
From page 247... ... B-69 Figure 66. Averages of the differences in Leq (5 min.) Read the entire page →
From page 248... ... B-70 Calm Inversion Class Figure 67 shows the averages of the average level differences between the Barrier and No Barrier microphones' levels for all the Calm Inversion groups with their error bars. The results at the three microphone pairs are like those for the Calm Lapse and Calm Neutral groups. Read the entire page →
From page 249... ... B-71 Figure 67. Averages of the differences in Leq (5 min.) Read the entire page →
From page 250... ... B-72 Downwind Lapse Class Figure 68 shows the averages of the average level differences between the Barrier and No Barrier microphones. There were only two nonoverlapping 5-minute periods of Downwind Lapse data. Read the entire page →
From page 251... ... B-73 Figure 68. Averages of the differences in Leq (5 min.) Read the entire page →
From page 252... ... B-74 Comparison of Downwind Lapse and Calm Neutral Results Figure 69 compares the differences in one-third octave band levels for the Calm Neutral class and for the limited data in the Downwind Lapse class. As noted, there were only two nonoverlapping 5-minute periods of Downwind Lapse data, so any conclusions should be viewed with caution. Read the entire page →
From page 253... ... B-75 Figure 69. Differences in the Downwind Lapse average differences and the Calm Neutral average differences (Leq (5 min.) Read the entire page →
From page 254... ... B-76 Additional Sound Level Analysis for I-70 – Ln Descriptors In addition to the examination of the differences in levels for the equivalent pairs of running 5-minute Leq data, the differences in the Ln descriptors for the overall data without segregation into equivalent periods were investigated. The focus was on the possible change in the background level in the presence of the noise barrier. Read the entire page →
From page 255... ... B-77 Figure 71. Differences in broadband A-weighted 5-minute L90, L99 and Leq, I-70, BarRef01 and NoBarRef02. Read the entire page →
From page 256... ... B-78 Figure 72. Read the entire page →
From page 257... ... B-79 Figure 74. Read the entire page →
From page 258... ... B-80 BarRef01 levels are higher than the NoBarRef02 levels and blue means that NoBarRef02 is higher. In the graph, time runs from top to bottom (increasing as one moves down each figure, with each row representing the starting minute of a running 5-minute period) Read the entire page →
From page 259... ... B-81 Figure 77. I-70 Differences in Ln (5 min.) Read the entire page →
From page 260... ... B-82 2. For the community side positions, where the microphones are placed on the opposite side of the roadway from the barrier at the Barrier site and the same positions for the No Barrier site, it is difficult to see any differences in the shapes and shades of the hottest spots (dark red) Read the entire page →
From page 261... ... B-83 Figure 79. I-70 5-minute spectrograms; top: BarRef01, bottom: NoBarRef02, start time 15:30. Read the entire page →
From page 262... ... B-84 Figure 80. I-70 5-minute spectrograms; top: BarCom03, bottom: NoBarCom05, start time 15:30. Read the entire page →
From page 263... ... B-85 Figure 81. I-70 5-minute spectrograms; top: BarCom04, bottom: NoBarCom06, start time 15:30. Read the entire page →
From page 264... ... B-86 Figure 82. I-70 5-minute spectrograms; top: BarRef01, bottom: NoBarRef02, start time 17:20. Read the entire page →
From page 265... ... B-87 Figure 83. I-70 5-minute spectrograms; top: BarCom03, bottom: NoBarCom05, start time 17:20. Read the entire page →
From page 266... ... B-88 Figure 84. I-70 5-minute spectrograms; top: BarCom04, bottom: NoBarCom06, start time 17:20. Read the entire page →
From page 267... ... B-89 Figure 85. I-70 heavy truck pass-by event at ~17:45 spectrograms; top: BarCom03, bottom: NoBarCom05. Read the entire page →
From page 268... ... B-90 Figure 86. I-70 heavy truck pass-by event at ~17:45 spectrograms; top: BarCom04, bottom: NoBarCom06. Read the entire page →
From page 269... ... B-91 Figure 87. I-70 two heavy truck pass-by events at ~17:50 spectrograms; top: BarCom03, bottom: NoBarCom05. Read the entire page →
From page 270... ... B-92 Figure 88. I-70 two heavy truck pass-by events at ~17:50 spectrograms; top: BarCom04, bottom: NoBarCom06. Read the entire page →
From page 271... ... B-93 C H A P T E R B - 5 Results – I-270, Grove City, Ohio (Location OH-3) As shown in Figure 89, the I-270 location in Grove City, Ohio, is a six-lane freeway. Read the entire page →
From page 272... ... B-94 Figure 89. I-270 No Barrier view (top left) Read the entire page →
From page 273... ... B-95 Figure 90. I-270 microphone positions. Read the entire page →
From page 274... ... B-96 Figure 91. Read the entire page →
From page 275... ... B-97 Figure 92 shows cross-sections at the Barrier and No Barrier sites. The cross-sections are similar at the BarCom03 and NoBarCom05 locations adjacent to I-270, but they are different moving back to the BarCom04 and NoBarCom06 positions farther from I-270. Read the entire page →
From page 276... ... B-98 property line boundary to the east. No differences could be discerned in the characteristics of the noise at the NoBarCom06 position compared to the BarCom04 position. Read the entire page →
From page 277... ... B-99 Figure 93. Running Leq (5 min.) Read the entire page →
From page 278... ... B-100 Figure 95. Running Leq (5 min.) Read the entire page →
From page 279... ... B-101 Figure 97. Differences in running Leq (5 min.) Read the entire page →
From page 280... ... B-102 Figure 99. Running Leq (5 min.) Read the entire page →
From page 281... ... B-103 allowable variation in the NoBarRef02 Leq (5 min.) between the periods in a group was 0 dB in most cases and 0.1 dB in one case, and the allowable average speed differences between periods was 5 mph. Read the entire page →
From page 282... ... Figure 102. Equivalent 5-minute periods for Calm Inversion groups at I-270. Read the entire page →
From page 283... ... B-105 Table 10. Two-way traffic volumes in 5-minute periods, by equivalent group Calm Inversion conditions, sorted by factored hourly volume, I-270. Read the entire page →
From page 284... ... B-106 Figure 103. Sample sound pressure level spectra for NoBarRef02, I-270, Calm Inversion group CIG24-1 02:15-02:20 (Leq (5 min.) Read the entire page →
From page 285... ... B-107 Figure 104. Sample sound pressure level spectra for BarCom03 and NoBarCom05, I-270, Calm Inversion group CIG-24-1 02:15-02:20 (Leq (5 min.) Read the entire page →
From page 286... ... B-108 Figure 105. Sample sound pressure level spectra for BarCom04 and NoBarCom06, I-270, Calm Inversion group CIG-24-1 02:15-02:20 (Leq (5 min.) Read the entire page →
From page 287... ... B-109 individual groups of equivalent periods, with some differences likely related to background noise and the uniqueness of vehicle noise sources in each period. Figure 106 shows in the upper graph the differences in levels between BarCom03 and NoBarCom05, both of which were close to the road and 5 ft. Read the entire page →
From page 288... ... B-110 Figure 106. Averages of the differences in Leq (5 min.) Read the entire page →
From page 289... ... B-111 Figure 107. Read the entire page →
From page 290... ... B-112 Figure 108. Read the entire page →
From page 291... ... B-113 Figure 110. Read the entire page →
From page 292... ... B-114 NoBarCom05. Figure 112. Read the entire page →
From page 293... ... B-115 Data Analysis – Spectrograms for I-270 Spectrograms show the frequency content of sound as a function of time. This section presents results of the spectrogram analysis for the I-270 Ohio site. Read the entire page →
From page 294... ... B-116 In general, sound levels opposite the absorptive noise Barrier at the I-270 site are lower than those with No Barrier over a broad range of frequencies. The observed differences are subtle for the microphone positions close to the road and more apparent farther from the road. Read the entire page →
From page 295... ... B-117 Figure 114. I-270 5-minute spectrograms; top: BarCom03, bottom: NoBarCom05, start time 00:40. Read the entire page →
From page 296... ... B-118 Figure 115. I-270 5-minute spectrograms; top: BarCom04, bottom: NoBarCom06, start time 00:40. Read the entire page →
From page 297... ... B-119 Figure 116. I-270 5-minute spectrograms; top: BarCom03, bottom: NoBarCom05, start time 02:10. Read the entire page →
From page 298... ... B-120 Figure 117. I-270 5-minute spectrograms; top: BarCom04, bottom: NoBarCom06, start time 02:10. Read the entire page →
From page 299... ... B-121 Figure 118. I-270 heavy truck pass-by event at ~02:38 spectrograms; top: BarCom03, bottom: NoBarCom05. Read the entire page →
From page 300... ... B-122 Figure 119. heavy truck pass-by event at ~02:38 spectrograms; top: BarCom04, bottom: NoBarCom06. Read the entire page →
From page 301... ... B-123 Figure 120. automobile pass-by event at ~02:40 spectrograms; top: BarCom03, bottom: NoBarCom05. Read the entire page →
From page 302... ... B-124 Figure 121. I-270 automobile pass-by event at ~02:40 spectrograms; top: BarCom04, bottom: NoBarCom06. Read the entire page →
From page 303... ... C-1 Comparison of Phase 1 and Phase 2 Results A P P E N D I X C William Bowlby BowlBy & AssociAtes, inc. Franklin, TN Judy Rochat ATS Consulting Pasadena, CA Ken Kaliski RSG White River Junction, VT Read the entire page →
From page 304... ... CONTENTS CHAPTER C-1 ..................................................................................................................................... C-3 Introduction to Appendix C ................................................................................................................................... Read the entire page →

From page 181...

... B-3 C H A P T E R B - 1 Introduction to Appendix B This appendix presents the details of the Phase 2 research data collection and analysis at three soundabsorbing, single-barrier locations. It does not provide background on the subject, data collection and analysis protocols, comparison to the Phase 1 results, overall findings, applications, recommendations, or suggested research.