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From page 152... ... B - ii C O N T E N T S CHAPTER B-1 .................................................................................................................................. B-1 Introduction to Appendix B................................................................................................................................... Read the entire page →
From page 153... ... B - iii List of Figures Figure 1. Plan view of the relationship between direct and reflected sound paths to a receptor across the highway from a noise barrier. Read the entire page →
From page 154... ... B - iv Figure 26. Averages of the differences in Leq(5min) Read the entire page →
From page 155... ... B - v Figure 53. Running Leq(5min) Read the entire page →
From page 156... ... B - vi Figure 79. Running Leq(5min) Read the entire page →
From page 157... ... B - vii Figure 101. I-90 spectrograms for a third heavy truck on northbound (barrier) Read the entire page →
From page 158... ... B - viii Figure 128. Differences in broadband A-weighted 5-min L90, L99 and Leq, SR-71, BarCom04 and NoBarCom06. Read the entire page →
From page 159... ... B - ix Figure 157. Sample sound pressure level spectra for BarRef01 and NoBarRef02, MD-5, Calm Neutral Group CNG-3-4, 20:17 (Leq(5min) Read the entire page →
From page 160... ... B - x Figure 177. Differences in broadband A-weighted 5-min L90, L99 and Leq, MD-5, BarRef01 and NoBarRef02. Read the entire page →
From page 161... ... B - xi List of Tables Table 1. Selected locations. Read the entire page →
From page 162... ... B - 1 C H A P T E R B - 1 Introduction to Appendix B This appendix presents the details of the research data collection and analysis protocols and the results at five studied single-barrier locations. It does not provide background on the subject, overall findings, applications, recommendations or suggested research. Read the entire page →
From page 163... ... B - 2 the 5-minute periods found to be equivalent to each other in terms of source and meteorological class are identified and studied for 1/3 octave band sound pressure level differences at the microphone pairs. Sample 1/3 octave band unweighted sound pressure level spectra are also presented for comparison at the microphone pairs. Read the entire page →
From page 164... ... B - 3 C H A P T E R B - 2 Research Approach Study Location Selection Criteria and Process The location selection criteria were developed primarily based on the information needed for judging if a Barrier site and its potentially "equivalent" No Barrier site are indeed equivalent. The criteria were incorporated in a Preliminary Site Evaluation Form prepared by the researchers. Read the entire page →
From page 165... ... B - 4 7. RSG-3, US 3/FE Everett Turnpike, Nashua, NH. Read the entire page →
From page 166... ... B - 5 Table 1. Selected locations. Read the entire page →
From page 167... ... B - 6 The selected locations provided good opportunities to study the noise barrier reflections issue. Each location is described briefly below. Read the entire page →
From page 168... ... B - 7 single family residential lots, one at 5 ft above ground and one at 12 ft above ground so that both were approximately 14 ft below the pavement. The houses precluded measuring farther from the road. Read the entire page →
From page 169... ... B - 8 reflective concrete block atop a 6-ft high earthen berm wall near the right-of-way line at distance of approximately 50 ft from the center of the near travel lane. See Figure 5. Read the entire page →
From page 170... ... B - 9 Data Collection Protocol Three types of data analysis were used in this study: • FHWA Method (based on the Indirect Measured procedure in Chapter 6 of FHWA's Measurement of Highway-Related Noise (Ref. Read the entire page →
From page 171... ... B - 10 To accomplish this assignment of the data into periods, the initial goal was to count and classify traffic at each site from the video recording and to merge that data with the speed data to determine periods of equivalent source conditions over the four-hour measurement period, in what will be called "traffic classes." Unfortunately, the video data was not collected at the BA-3 Briley Parkway site. An alternative method of determining period equivalency – based on the reference microphone sound levels and the average speeds by direction of travel – was found that worked very well and was adopted for the rest of the study. Read the entire page →
From page 172... ... B - 11 determining the sound level range in a sample period and in diagnosing data on individual passbys and the possible sustaining of the background level due to sound reflections off the barrier. Meteorological Data At each location, the meteorological station was set up in an open area near the No Barrier site. Read the entire page →
From page 173... ... B - 12 lane, as expected. For consistency, for roads with more than two lanes in each direction – the condition at both locations – the majority of speeds were measured in the second lane from the outside. Read the entire page →
From page 174... ... B - 13 worksheets for each microphone position (BarRef01, NoBarRef02, BarCom03, BarCom04, NoBarCom05 and NoBarCom06) Read the entire page →
From page 175... ... B - 14 minute running averages gives more flexibility when trying to determine periods that have equivalent sources and meteorological conditions. Each 5-minute period was assigned to a meteorological class, based on a requirement that at least three of the five minutes be in the same class. Read the entire page →
From page 176... ... B - 15 The data analysis procedure in Measurement of Highway-Related Noise was used, with some adjustment. The first step was to determine any needed calibration adjustments prior to data analysis. Read the entire page →
From page 177... ... B - 16 SLI03,j = LBarCom03(j) Read the entire page →
From page 178... ... B - 17 show the effect of the barrier noise reflected back across the highway to communities opposite a noise barrier. At some of the sites, the reference microphones were strategically placed between the road and the barrier to capture barrier reflections on the barrier side of the highway. Read the entire page →
From page 179... ... B - 18 where the weighting kernel g(z) is an exponential function that gently slopes upward with increasing frequency, 𝑔𝑔(𝑧𝑧) Read the entire page →
From page 180... ... B - 19 is the "masking depth", and N' represents the specific Loudness in any one critical band. The term 𝑁𝑁1′ is the 99th percentile loudness (exceeded 1% of the time) Read the entire page →
From page 181... ... B - 20 • Mean Sharpness (S) in acums, • Mean Fluctuation Strength (F) Read the entire page →
From page 182... ... B - 21 For each one-minute interval, the resulting sound quality metrics were combined using the equations for Unbiased Annoyance, Psychoacoustic Annoyance, and Category Scale of Annoyance within MS Excel. The resulting time series were plotted in pairs: the low-height microphones (BarCom03 and NoBarCom05) Read the entire page →
From page 183... ... B - 22 C H A P T E R B - 3 Results - I-24, Murfreesboro, TN (Location BA-1) The I-24 measurements were conducted from 13:13 to 17:20 on August 13, 2014 (all times will be based on a 24-hour clock) Read the entire page →
From page 184... ... B - 23 A concrete median barrier at both the Barrier and No Barrier sites shielded the view of the vehicle tires and automobile engines and exhausts at the 5-ft high BarCom03 and NoBarCom05 microphones. It could have also shielded the BarCom03 microphone from some of the reflected noise. Read the entire page →
From page 185... ... B - 24 Figure 8. Cross-sections at the I-24 Barrier (top) Read the entire page →
From page 186... ... B - 25 eastbound traffic slowed in the 16:55-17:01 period. At the No Barrier site, Observer 2 noticed that the eastbound traffic appeared to be slowing around 15:46 for a minute, again briefly at 15:50, and again briefly at 16:24. Read the entire page →
From page 187... ... B - 26 • BarRef01 and NoBarRef02 - Figure 9 (unweighted) and Figure 10(A-weighted) Read the entire page →
From page 188... ... B - 27 Figure 10. Running Leq(5min) Read the entire page →
From page 189... ... B - 28 Figure 12. Running Leq(5min) Read the entire page →
From page 190... ... B - 29 Figure 14. Differences in running Leq(5min) Read the entire page →
From page 191... ... B - 30 Figure 16. Running Leq(5min) Read the entire page →
From page 192... ... B - 31 Figure 18 shows these groupings graphically for the Upwind Lapse class. The times along the top represent the starting minute of each 5-minute period. Read the entire page →
From page 193... ... B - 32 Figure 18. Equivalent 5-minute periods for Upwind Lapse groups at I-24. Read the entire page →
From page 194... ... B - 33 Figure 19. Equivalent 5-minute periods for Calm Lapse groups at I-24. Read the entire page →
From page 195... ... B - 34 ULG-10-1 504 550 579 598 642 6,895 ULG-9-6 568 552 539 570 592 617 6,876 ULG-8-2 507 513 539 562 613 618 6,704 ULG-8-1 507 513 535 562 613 618 6,696 ULG-7-1 461 557 556 657 6,693 ULG-12-1 488 554 623 6,660 ULG-7-2 461 522 556 657 6,588 ULG-12-2 488 547 610 6,580 ULG-6-2 462 555 543 604 6,492 ULG-11-2 489 561 573 6,492 ULG-11-1 489 561 572 6,488 ULG-6-1 449 543 604 6,384 ULG-6-3 433 543 604 6,320 ULG-4-1 511 497 497 552 546 6,247 ULG-4-2 494 497 497 552 546 6,206 ULG-3-6 521 514 501 6,144 ULG-3-5 521 494 501 6,064 ULG-2-1 479 475 552 6,024 ULG-3-3 488 514 501 6,012 ULG-3-4 488 514 501 6,012 ULG-5-1 437 505 504 539 5,955 ULG-3-2 481 476 514 501 5,916 ULG-3-1 481 494 501 5,904 ULG-1-1 425 491 495 511 5,766 ULG-1-2 425 491 495 489 5,700 Calm Lapse CLG-2-2 526 583 583 668 7,080 CLG-5-1 481 611 642 616 7,050 CLG-2-1 526 583 629 6,952 CLG-6-1 523 494 611 610 651 6,934 CLG-6-2 523 494 611 610 618 6,854 CLG-5-2 481 471 611 642 616 6,770 CLG-5-3 481 488 588 642 616 6,756 CLG-3-2 526 523 523 623 6,585 CLG-4-1 502 503 511 593 585 584 6,556 CLG-3-1 526 491 523 623 6,489 CLG-4-2 502 503 511 593 585 6,466 CLG-4-3 502 503 511 593 584 6,463 CLG-1-1 470 493 598 6,244 Calm Neutral CNG-2-1 659 686 708 8,212 CNG-2-2 659 665 680 8,016 CNG-1-1 599 722 680 8,004 CNG-1-2 599 662 680 7,764 Sound Pressure Level Spectra Before discussing the differences in levels between the Barrier and No Barrier sites, typical sound pressure level spectra are shown to give some perspective on the data upon which the differences are based. One of the 5-minute periods in the one of the Upwind Lapse groups was chosen as typical. Read the entire page →
From page 196... ... B - 35 Figure 21. Sample sound pressure level spectra for BarRef01 and NoBarRef02, I-24, Upwind Lapse group ULG-3-2, 13:26-13:31 (Leq(5min) Read the entire page →
From page 197... ... B - 36 Figure 22. Sample sound pressure level spectra for BarCom03 and NoBarCom05, I-24, Upwind Lapse group ULG-3-2, 13:26-13:31 (Leq(5min) Read the entire page →
From page 198... ... B - 37 Figure 23. Sample sound pressure level spectra for BarCom04 and NoBarCom06, I-24, Upwind Lapse group ULG-3-2, 13:26-13:31 (Leq(5min) Read the entire page →
From page 199... ... B - 38 Each graph shows the averages of the average level differences for the A-weighted sound level, the unweighted sound pressure level and the 1/3 octave band sound pressure levels from 20 Hz to 10 kHz. Graphs for all of the individual Upwind Lapse groups are in spreadsheet files in the project record. Read the entire page →
From page 200... ... B - 39 Figure 24. Averages of the differences in Leq(5min) Read the entire page →
From page 201... ... B - 40 Calm Lapse Class Figure 25 shows the averages of the average level differences between the Barrier and No Barrier microphones' levels for all of the Calm Lapse groups, with error bars, in the same manner as the Upwind Lapse groups. Other than some minor variations, the Calm Lapse differences are very similar to those for the Downwind Lapse class for all three microphone pairs. Read the entire page →
From page 202... ... B - 41 Figure 25. Averages of the differences in Leq(5min) Read the entire page →
From page 203... ... B - 42 Calm Neutral Class Figure 26 shows the averages of the average level differences between the Barrier and No Barrier microphones' levels for all of the Calm Neutral groups, with their error bars. Graphs for all of the individual Calm Neutral groups are in spreadsheet files in the project record. Read the entire page →
From page 204... ... B - 43 Figure 26. Averages of the differences in Leq(5min) Read the entire page →
From page 205... ... B - 44 Comparison of Upwind Lapse and Calm Lapse Results Figure 27 compares the differences in level for the Upwind Lapse and Calm Lapse classes for the six microphone positions. The data values are the average Upwind Lapse differences minus the average Calm Lapse differences for each frequency band. Read the entire page →
From page 206... ... B - 45 Figure 27. Differences in the Upwind Lapse average differences and the Calm Lapse average differences (Leq(5min) Read the entire page →
From page 207... ... B - 46 Additional Sound Level Analysis for I-24 – Ln Descriptors In addition to the examination of the differences in levels for the equivalent pairs of running 5-min Leq data, an investigation was made of the differences in the Ln descriptors for the overall data without segregation into equivalent periods, focusing on the possible change in the background level in the presence of the noise barrier. Figure 28 presents the L90(5min) Read the entire page →
From page 208... ... B - 47 Figure 28. Read the entire page →
From page 209... ... B - 48 Figure 30. Read the entire page →
From page 210... ... B - 49 Figure 32. Read the entire page →
From page 211... ... B - 50 The above graphs were for the broadband A-weighted sound levels and unweighted sound pressure levels only. Figure 34, shown below, broadens the analysis to include the individual 1/3 octave bands by use of color shading. Read the entire page →
From page 212... ... B - 51 Figure 36. I-24 Differences in Ln(5min) Read the entire page →
From page 213... ... B - 52 reference positions and the high microphone positions, comparing the Barrier and No Barrier sites. Figure 41shows the same for the low microphone positions. Read the entire page →
From page 214... ... B - 53 Figure 38. I-24 5-minute spectrograms; top to bottom: BarRef01, NoBarRef02, and high mics (BarCom04 and NoBarCom06) Read the entire page →
From page 215... ... B - 54 Figure 39. I-24 5-minute spectrograms; top to bottom: low mic BarCom03 and NoBarCom05; for Upwind Lapse group ULG-9-1, start time 14:45. Read the entire page →
From page 216... ... B - 55 Figure 40. I-24 5-minute spectrograms; top to bottom: BarRef01, NoBarRef02, high mics (BarCom04 and NoBarCom06) Read the entire page →
From page 217... ... B - 56 Figure 41. I-24 5-minute spectrograms; top to bottom: lows mics BarCom03 and NoBarCom05; for Calm Lapse group CLG-6-1, start time 15:56. Read the entire page →
From page 218... ... B - 57 Figure 42. I-24 5-minute spectrograms; top to bottom: BarRef01, NoBarRef02, high mics (BarCom04 and NoBarCom06) Read the entire page →
From page 219... ... B - 58 Figure 43. I-24 5-minute spectrograms; top to bottom: lows mics BarCom03 and NoBarCom05; for Calm Neutral group CNG-2-1, start time 17:05. Read the entire page →
From page 220... ... B - 59 Figure 44. I-24 spectrograms for a group of heavy trucks; top to bottom: BarRef01, NoBarRef02. Read the entire page →
From page 221... ... B - 60 Data Analysis - Psychoacoustics for I-24 Descriptive statistics for the computed annoyance metrics at I-24 are summarized in Table 6. The associated histograms in each of the subsequent Figures relate the distribution of magnitudes for each metric at each microphone to the descriptive statistics in the Table. Read the entire page →
From page 222... ... B - 61 NoBarCom06 44.2 1.7 0.083 0.826 Figure 46. Unbiased annoyance metric vs. Read the entire page →
From page 223... ... B - 62 Figure 48. Category scale of annoyance vs. Read the entire page →
From page 224... ... B - 63 C H A P T E R B - 4 Results - Briley Parkway (SR-155) , Nashville, TN (Location BA-3) Read the entire page →
From page 225... ... B - 64 Figure 49. Briley microphone positions. Read the entire page →
From page 226... ... B - 65 Measurement Observations Traffic was observed from an overpass about a half-mile west of the Barrier site. Automobiles and heavy trucks dominated the flow, while medium trucks, buses and motorcycles were infrequent. Read the entire page →
From page 227... ... B - 66 Starting at the NoBarCom05/06 site at the beginning of the measurements, Observer 3 noted that it was easy to identify eastbound passages of heavy trucks, although it could not always be determined if there was a single truck or multiple trucks passing. Trucks in the outside eastbound lane were visible from a position located 5 ft above the ground near NoBarCom05. Read the entire page →
From page 228... ... B - 67 weighted sound levels at BarCom03 are generally 1.5 dB to 2 dB lower than the NoBarCom05 levels in the first three hours of the measurement and 2 dB to 3 dB lower in the last hour. Figure 57 shows these level differences. Read the entire page →
From page 229... ... B - 68 Figure 51. Running Leq(5min) Read the entire page →
From page 230... ... B - 69 Figure 53. Running Leq(5min) Read the entire page →
From page 231... ... B - 70 Figure 55. Running Leq(5min) Read the entire page →
From page 232... ... B - 71 Figure 57. Difference in running Leq(5min) Read the entire page →
From page 233... ... B - 72 Data Analysis for Briley Parkway - FHWA Method All of the Briley Parkway data was in the Calm wind class and in the Lapse, Neutral or Inversion temperature gradient classes. Each of the four Calm Lapse groups had three equivalent 5-minute periods. Read the entire page →
From page 234... ... B - 73 Figure 61. Equivalent 5-minute periods for Calm Inversion groups at Briley Parkway. Read the entire page →
From page 235... ... B - 74 Calm Lapse Class Figure 62 shows an example of the averages of the sound level differences across all of the Calm Lapse groups. The lower graph of Figure 62 compares the upper microphones at the Briley Barrier and No Barrier sites: BarCom04 and NoBarCom06. Read the entire page →
From page 236... ... B - 75 31.5 Hz through 100 Hz bands by as much as 6 dB at 63 Hz. However, BarCom03 shows lower levels than NoBarCom05 for the rest of the frequencies up through 8 kHz. Read the entire page →
From page 237... ... B - 76 Figure 63. Sample sound pressure level spectra for BarCom03 and NoBarCom05, I-24, Calm Neutral group CNG-1-4, 17:25-17:30 (Leq(5min) Read the entire page →
From page 238... ... B - 77 Figure 64. Sample sound pressure level spectra for BarCom04 and NoBarCom06, I-24, Calm Neutral group CNG-1-4, 17:25-17:30 (Leq(5min) Read the entire page →
From page 239... ... B - 78 band, the levels in the rest of the bands were lower at BarCom03 compared to NoBarCom05, ranging from as little as less than a decibel at 800 Hz to approximately 5 dB at 160 Hz, 200 Hz and 250 Hz (as well as by 7 dB at 8 kHz, which was due to the insect noise at the No Barrier site) Read the entire page →
From page 240... ... B - 79 Calm Inversion Class The last set of results for Briley is for a sample from the Calm Inversion group. Figure 66 and Figure 67 show the spectral plots for BarCom03 and NoBarCom05 and then BarCom04 and NoBarCom06. Read the entire page →
From page 241... ... B - 80 Figure 67. Sample Sound Pressure Level Spectra for BarCom04 and NoBarCom06, Briley, Calm Inversion Group CIG-6-1, 18:58-19:03 (Leq(5min) Read the entire page →
From page 242... ... B - 81 respectively, than NoBarCom06; and (4) at 10 kHz, the NoBarCom06 level was 5 dB higher than BarCom04, compared to being 6 dB lower in the Calm Neutral example. Read the entire page →
From page 243... ... B - 82 Additional Sound Level Analysis for Briley Parkway – Ln Descriptors Because of issues with loud insect noise at the No Barrier site, the Ln analysis was not done at the Briley site. Data Analysis for Briley Parkway - Spectrograms Spectrograms show the frequency content of sound as a function of time. Read the entire page →
From page 244... ... B - 83 Figure 69. Spectrogram for a heavy truck eastbound (example 1) Read the entire page →
From page 245... ... B - 84 Figure 70. Spectrogram for a heavy truck eastbound (example 2) Read the entire page →
From page 246... ... B - 85 Data Analysis for Briley Parkway – Psychoacoustics The audio recordings for the monitoring period at Briley Parkway were too contaminated with electronic noise to perform meaningful psychoacoustical analyses. Therefore, they are omitted from this report. Read the entire page →
From page 247... ... B - 86 C H A P T E R B - 5 Results - I-90, Rockford, IL (Location SID-1) The measurements on I-90 in Rockford, IL took place on Dec. Read the entire page →
From page 248... ... B - 87 Figure 71. I-90 microphone positions. Read the entire page →
From page 249... ... B - 88 Measurement Observations Winds were very low during the measurement period. There was also very little noise contamination, with only an airplane overflight and a police siren. Read the entire page →
From page 250... ... B - 89 At all of the microphones, as time passed the Leq(5min) dropped slowly, on the order of 1 dB to 2 dB, over the 4-hour period. Read the entire page →
From page 251... ... B - 90 Figure 75. Differences in running Leq(5min) Read the entire page →
From page 252... ... B - 91 Figure 77. Running Leq(5min) Read the entire page →
From page 253... ... B - 92 Figure 79. Running Leq(5min) Read the entire page →
From page 254... ... B - 93 Figure 81. Differences in running Leq(5min) Read the entire page →
From page 255... ... B - 94 Group ID Starting Time of 5-minute Periods 13 :0 7 13 :0 9 13 :1 0 13 :2 0 13 :2 4 13 :2 7 13 :2 9 13 :3 6 13 :4 2 13 :4 3 13 :4 4 13 :4 5 13 :5 0 14 :0 7 14 :1 4 14 :1 5 14 :1 6 14 :3 8 14 :4 3 14 :4 4 14 :4 6 DLG-1-1 1 1 1 1 DLG-1-2 1 1 1 1 DLG-2-1 1 1 1 DLG-2-2 1 1 1 DLG-2-3 1 1 1 DLG-2-4 1 1 1 DLG-2-5 1 1 1 DLG-2-6 1 1 1 DLG-3-1 1 1 1 1 1 DLG-3-2 1 1 1 1 1 DLG-4-1 1 1 1 DLG-4-2 1 1 1 Figure 82. Equivalent 5-minute periods for Downwind Lapse groups at I-90. Read the entire page →
From page 256... ... B - 95 DLG-2-6 421 413 402 4,944 DLG-1-1 410 412 408 387 4,851 DLG-1-2 410 412 384 387 4,779 Calm Neutral CNG-1-1 389 436 464 5,156 CNG-1-2 389 436 458 5,132 CNG-1-3 389 415 464 5,072 CNG-1-4 389 415 458 5,048 Sound Pressure Level Spectra Before discussing the differences in levels between the Barrier and No Barrier sites, typical sound pressure level spectra are shown to give some perspective on the data on which the differences are based. One of the 5-minute periods in the one of the Calm Neutral Groups was chosen as typical. Read the entire page →
From page 257... ... B - 96 Figure 84. Sample sound pressure level spectra for BarRef01 and NoBarRef02, I-90, Calm Neutral class, CNG-1-1, Period 15:37 (Leq(5min) Read the entire page →
From page 258... ... B - 97 Figure 85. Sample sound pressure level spectra for BarCom03 and NoBarCom05, I-90, Calm Neutral class, CNG-1-1, Period 15:37 (Leq(5min) Read the entire page →
From page 259... ... B - 98 Figure 86. Sample sound pressure level spectra for BarCom04 and NoBarCom06, I-90, Calm Neutral class, CNG-1-1, Period 15:37 (Leq(5min) Read the entire page →
From page 260... ... B - 99 trends across the 1/3 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 87 shows in the upper graph that, in general, the BarRef01 levels are 0 dB to 1 dB higher than the NoBarRef02 levels at 400 Hz and below. Read the entire page →
From page 261... ... B - 100 Figure 87. Averages of the differences in Leq(5min) Read the entire page →
From page 262... ... B - 101 Downwind Lapse Class Figure 88 shows the averages of the differences in the Barrier and No Barrier microphones' levels for all of the Downwind Lapse groups, with their error bars, in the same manner as the Calm Neutral groups. Each graph shows the averages of the average level differences for the A-weighted sound level, the unweighted sound pressure level and the 1/3 octave band sound pressure levels from 20 Hz to 10 kHz. Read the entire page →
From page 263... ... B - 102 Figure 88. Averages of the differences in Leq(5min) Read the entire page →
From page 264... ... B - 103 Comparison of Downwind Lapse (community microphones) and Calm Neutral Results and Upwind Lapse (reference microphones) Read the entire page →
From page 265... ... B - 104 Figure 89. Differences in the Calm Neutral average differences and the Downwind Lapse average differences (Leq(5min) Read the entire page →
From page 266... ... B - 105 Additional Sound Level Analysis for I-90 – Ln Descriptors Figure 90 presents the L90(5min) Read the entire page →
From page 267... ... B - 106 Figure 90. Read the entire page →
From page 268... ... B - 107 Figure 92. Read the entire page →
From page 269... ... B - 108 Figure 94. Read the entire page →
From page 270... ... B - 109 The above graphs were for the broadband A-weighted sound levels and unweighted sound pressure levels only. Figure 96, shown below, broadens the analysis to include the individual 1/3 octave bands by use of color shading. Read the entire page →
From page 271... ... B - 110 Figure 97. I-90 Differences in Ln(5min) Read the entire page →
From page 272... ... B - 111 Figure 99 shows two plots of a heavy truck traveling southbound. The pass-by event is around 13:29:36 at the barrier site and around 13:29:43 at the No Barrier site. Read the entire page →
From page 273... ... B - 112 Figure 99. I-90 spectrograms for a heavy truck on southbound (community) Read the entire page →
From page 274... ... B - 113 Figure 100. I-90 spectrograms for a second heavy truck on southbound (community) Read the entire page →
From page 275... ... B - 114 Figure 101. I-90 spectrograms for a third heavy truck on northbound (barrier) Read the entire page →
From page 276... ... B - 115 similar results. The farther microphones (BarCom04 and NoBarCom06) Read the entire page →
From page 277... ... B - 116 Figure 102. I-90 spectrograms for an hour-long block of data from 15:30 to 16:30: top is BarCom03; bottom is NoBarCom05. Read the entire page →
From page 278... ... B - 117 Data Analysis for I-90 - Psychoacoustics Descriptive statistics for the computed annoyance metrics at I-90 are summarized in Table 10. The associated histograms in each of the subsequent Figures relate the distribution of magnitudes for each metric at each microphone to the descriptive statistics in the Table. Read the entire page →
From page 279... ... B - 118 Figure 104. Unbiased annoyance vs. Read the entire page →
From page 280... ... B - 119 Figure 106. Category scale of annoyance vs. Read the entire page →
From page 281... ... B - 120 C H A P T E R B - 6 Results – SR-71, Chino Hills, CA (Location ATS-3) On January 28, 2015, data was successfully collected at the fourth location, SR-71, in Chino Hills, California. Read the entire page →
From page 282... ... B - 121 Figure 108. Cross-sections at the SR-71 Barrier (top) Read the entire page →
From page 283... ... B - 122 position) and intervening ground (e.g., if the close microphones were placed in line with the far microphone, the ground between the highway noise source and BarCom03 would have included more pavement than for NoBarCom05 due to a merge lane; the close microphones were shifted south of where the merge lane ends) Read the entire page →
From page 284... ... B - 123 Measured Broadband Levels and Level Differences for SR-71 The running Leq(5min) 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 109 (unweighted) Read the entire page →
From page 285... ... B - 124 Figure 109. Running Leq(5min) Read the entire page →
From page 286... ... B - 125 Figure 111. Differences in running Leq(5min) Read the entire page →
From page 287... ... B - 126 Figure 113. Running Leq(5min) Read the entire page →
From page 288... ... B - 127 Figure 115. Running Leq(5min) Read the entire page →
From page 289... ... B - 128 Figure 117. Differences in running Leq(5min) Read the entire page →
From page 290... ... B - 129 Group ID Starting Time of 5-minute Periods 10 :2 3 10 :2 6 10 :3 9 10 :4 4 10 :5 1 10 :5 5 11 :3 5 11 :3 8 11 :4 0 11 :4 4 11 :4 6 12 :1 1 12 :4 5 12 :4 6 12 :4 8 12 :5 8 13 :0 9 13 :1 0 13 :2 1 DNG-1-1 1 1 1 DNG-2-1 1 1 1 DNG-2-2 1 1 1 DNG-3-1 1 1 1 1 DNG-3-2 1 1 1 DNG-3-3 1 1 1 Figure 118. Equivalent 5-minute periods for Downwind Neutral groups at SR-71. Read the entire page →
From page 291... ... B - 130 Figure 119. Sample sound pressure level spectra for BarRef01 and NoBarRef02, SR-71, Downwind Neutral group DNG-3-2, 11:38-11:43 (Leq(5min) Read the entire page →
From page 292... ... B - 131 Figure 120. Sample sound pressure level spectra for BarCom03 and NoBarCom05, SR-71, Downwind Neutral group DNG-3-2, 11:38-11:43 (Leq(5min) Read the entire page →
From page 293... ... B - 132 Figure 121. Sample sound pressure level spectra for BarCom04 and NoBarCom06, SR-71, Downwind Neutral group DNG-3-2, 11:38-11:43 (Leq(5min) Read the entire page →
From page 294... ... B - 133 individual groups of equivalent periods, with some differences likely related to background noise and the uniqueness of vehicle noise sources in each period. Figure 122 shows in the upper graph that the BarRef01 levels are higher than the NoBarRef02 levels at across virtually the entire spectrum, with exception of 8 kHz and 10 kHz. Read the entire page →
From page 295... ... B - 134 Figure 122. Averages of the differences in Leq(5min) Read the entire page →
From page 296... ... B - 135 Additional Sound Level Analysis for SR-71 – Ln Descriptors Figure 123 presents the L90(5min) Read the entire page →
From page 297... ... B - 136 The results are different for this microphone pair than most of the other pairs across the various study locations because these microphones are the farthest from the road. Read the entire page →
From page 298... ... B - 137 Figure 123. Read the entire page →
From page 299... ... B - 138 Figure 125. Read the entire page →
From page 300... ... B - 139 Figure 127. Read the entire page →
From page 301... ... B - 140 The above graphs were for the broadband A-weighted sound levels and unweighted sound pressure levels only. Figure 129 broadens the analysis to include the individual 1/3 octave bands by use of color shading, where brown means that the BarRef01 levels are higher than the NoBarRef02 levels and blue means that NoBarRef02 is higher. Read the entire page →
From page 302... ... B - 141 Figure 130. SR-71 Differences in Ln(5min) Read the entire page →
From page 303... ... B - 142 The traffic is the same at both sites and is based on traffic data measured at SR-71. For ground type, calculations were done with both hard and soft ground to determine the possible influence from either one. Read the entire page →
From page 304... ... B - 143 Figure 133. TNM modeling results: TNM soft ground (top) Read the entire page →
From page 305... ... B - 144 The barrier effect for both the heavy trucks and motorcycle can be seen in the spectrograms for the far microphones. For the barrier site, the hot spots are wider and taller for a broad range of frequencies. Read the entire page →
From page 306... ... B - 145 Figure 134. SR-71 spectrograms for heavy trucks on southbound (community) Read the entire page →
From page 307... ... B - 146 Figure 135. SR-71 spectrograms for motorcycle on southbound (community) Read the entire page →
From page 308... ... B - 147 In addition to examining vehicle pass-by events, spectrograms for blocks of data were also examined. Two examples are provided below for the far-distance microphones (400 ft) Read the entire page →
From page 309... ... B - 148 Figure 136. SR-71 spectrograms for 4-minute block of data in the morning at 09:49: top is BarCom04; bottom is NoBarCom06. Read the entire page →
From page 310... ... B - 149 Figure 137. S SR-71 spectrograms for 5-minute block of data in the morning at 12:45: top is BarCom04; bottom is NoBarCom06. Read the entire page →
From page 311... ... B - 150 Data Analysis for SR-71 - Psychoacoustics Descriptive statistics for the computed annoyance metrics at SR-71 are summarized in Table 13. The associated histograms in each of the subsequent Figures relate the distribution of magnitudes for each metric at each microphone to the descriptive statistics in the table. Read the entire page →
From page 312... ... B - 151 Figure 139. Unbiased Annoyance vs. Read the entire page →
From page 313... ... B - 152 Figure 141. Category scale of annoyance vs. Read the entire page →
From page 314... ... B - 153 C H A P T E R B - 7 Results – MD-5, Hughesville, MD (Location EA-5) The noise measurements at the last field site, MD-5 in Hughesville, Maryland were conducted on June 9, 2015. Read the entire page →
From page 315... ... B - 154 Figure 142. MD-5 microphone positions. Read the entire page →
From page 316... ... B - 155 Figure 143. Cross-sections at the MD-5 Barrier (top) Read the entire page →
From page 317... ... B - 156 moving over from southbound MD-5 to turn onto Carrico Mill Road were the likely cause of reduced speeds that were generally observed in the right lane of southbound MD-5. Left-hand turns out of the neighborhood from Carrico Mill Road onto northbound MD-5 occurred but were not a major traffic movement. Read the entire page →
From page 318... ... B - 157 At BarCom03 and BarCom04, more single vehicle passbys were captured during this time period. There was still a noticeable amount of heavy truck traffic but lighter traffic occurred overall for this measurement period. Read the entire page →
From page 319... ... B - 158 For most of the running Leq(5min) periods during both the afternoon and evening, the BarCom04 levels were higher than the NoBarCom06 levels. Read the entire page →
From page 320... ... B - 159 Figure 146. Differences in running Leq(5min) Read the entire page →
From page 321... ... B - 160 Figure 148. Running Leq(5min) Read the entire page →
From page 322... ... B - 161 Figure 150. Running Leq(5min) Read the entire page →
From page 323... ... B - 162 Figure 152. Differences in running Leq(5min) Read the entire page →
From page 324... ... B - 163 Speeds were much more consistent, ranging from averages of 56 mph to 63 mph for the Calm Inversion groups, 58 mph to 63 mph for both the Calm Neutral and Downwind Lapse groups, and 58 mph to 64 mph for the Downwind Neutral groups. Group ID Starting Time of 5-minute Periods 1 9: 55 1 9: 56 1 9: 57 1 9: 58 2 0: 00 2 0: 01 2 0: 16 2 0: 17 2 0: 19 2 0: 32 2 0: 34 2 0: 36 2 0: 37 2 0: 40 2 0: 43 2 0: 44 2 0: 45 2 1: 27 2 1: 28 CNG-1-1 1 1 1 CNG-2-1 1 1 1 CNG-3-1 1 1 1 1 CNG-3-2 1 1 1 1 1 CNG-3-3 1 1 1 1 CNG-3-4 1 1 1 1 CNG-4-1 1 1 1 CNG-4-2 1 1 1 1 CNG-4-3 1 1 1 CNG-4-4 1 1 1 1 Figure 153. Read the entire page →
From page 325... ... B - 164 Figure 155. Equivalent 5-minute periods for Downwind Lapse groups at MD-5. Read the entire page →
From page 326... ... B - 165 Group ID Starting Time of 5-minute Periods 2 0: 54 2 1: 00 2 1: 01 2 1: 07 2 1: 08 2 1: 09 2 1: 17 2 1: 19 2 1: 34 2 1: 35 2 1: 36 2 1: 37 2 1: 39 2 1: 40 2 1: 47 2 1: 55 2 2: 03 2 2: 33 2 2: 45 2 3: 12 2 3: 14 2 3: 15 2 3: 17 2 3: 21 2 3: 22 2 3: 25 2 3: 26 2 3: 28 2 3: 30 2 3: 31 2 3: 34 2 3: 36 2 3: 37 2 3: 38 2 3: 45 CIG-1-1 1 1 1 CIG-2-1 1 1 1 1 CIG-2-2 1 1 1 1 CIG-3-1 1 1 1 CIG-3-2 1 1 1 CIG-3-3 1 1 1 CIG-3-4 1 1 1 CIG-4-1 1 1 1 CIG-5-1 1 1 1 1 CIG-6-1 1 1 1 CIG-7-1 1 1 1 1 CIG-7-2 1 1 1 CIG-7-3 1 1 1 CIG-7-4 1 1 1 CIG-8-1 1 1 1 Figure 156. Equivalent 5-minute periods for Calm Inversion groups at MD-5. Read the entire page →
From page 327... ... B - 166 Table 15. Two-way traffic volumes in 5-minute periods, by equivalent group for Calm Inversion, Calm Neutral, Downwind Lapse and Downwind Neutral conditions, sorted by factored hourly volume, MD-5. Read the entire page →
From page 328... ... B - 167 DNG-2-1 181 187 249 178 178 2,335 DNG-1-2 156 188 167 233 2,232 DNG-1-1 156 188 167 217 2,184 DNG-2-2 172 187 178 178 2,145 Sound Pressure Level Spectra Before discussing the differences in levels between the Barrier and No Barrier sites, typical sound pressure level spectra are shown to give some perspective on the data on which the differences are based. One of the 5-minute periods in each of the four meteorological classes was chosen as typical. Read the entire page →
From page 329... ... B - 168 Figure 157. Sample sound pressure level spectra for BarRef01 and NoBarRef02, MD-5, Calm Neutral Group CNG-3-4, 20:17 (Leq(5min) Read the entire page →
From page 330... ... B - 169 Figure 158. Sample sound pressure level spectra for BarCom03 and NoBarCom05, MD-5, Calm Neutral Group CNG-3-4, 20:17 (Leq(5min) Read the entire page →
From page 331... ... B - 170 Figure 159. Sample sound pressure level spectra for BarCom04 and NoBarCom06, MD-5, Calm Neutral Group CNG-3-4, 20:17 (Leq(5min) Read the entire page →
From page 332... ... B - 171 Figure 160. Sample sound pressure level spectra for BarRef01 and NoBarRef02, MD-5, Downwind Neutral Group DNG-2-2, 13:14 (Leq(5min) Read the entire page →
From page 333... ... B - 172 Figure 161. Sample sound pressure level spectra for BarCom03 and NoBarCom05, MD-5, Downwind Neutral Group DNG-2-2, 13:14 (Leq(5min) Read the entire page →
From page 334... ... B - 173 Figure 162. Sample sound pressure level spectra for BarCom04 and NoBarCom06, MD-5, Downwind Neutral Group DNG-2-2, 13:14 (Leq(5min) Read the entire page →
From page 335... ... B - 174 Figure 163. Sample sound pressure level spectra for BarRef01 and NoBarRef02, MD-5, Downwind Lapse Group DLG-3-4, 13:13 (Leq(5min) Read the entire page →
From page 336... ... B - 175 Figure 164. Sample sound pressure level spectra for BarCom03 and NoBarCom05, MD-5, Downwind Lapse Group DLG-3-4, 13:13 (Leq(5min) Read the entire page →
From page 337... ... B - 176 Figure 165. Sample sound pressure level spectra for BarCom04 and NoBarCom06, MD-5, Downwind Lapse Group DLG-3-4, 13:13 (Leq(5min) Read the entire page →
From page 338... ... B - 177 Figure 166. Sample sound pressure level spectra for BarRef01 and NoBarRef02, MD-5, Calm Inversion Group CIG-3-4, 23:15 Leq(5min) Read the entire page →
From page 339... ... B - 178 Figure 167. Sample sound pressure level spectra for BarCom03 and NoBarCom05, MD-5, Calm Inversion Group CIG-3-4, 23:15 (Leq(5min) Read the entire page →
From page 340... ... B - 179 Figure 168. Sample sound pressure level spectra for BarCom04 and NoBarCom06, MD-5, Calm Inversion Group CIG-3-4, 23:15 Leq(5min) Read the entire page →
From page 341... ... B - 180 The next four figures show the averages of the differences in the Barrier and No Barrier microphones' levels for each of the four studied meteorological classes, with their error bars. The error bars are +/- one standard deviation for each average value. Read the entire page →
From page 342... ... B - 181 Figure 169. Averages of the differences in Leq(5min) Read the entire page →
From page 343... ... B - 182 Downwind Neutral Class Figure 170 shows the results for the Downwind Neutral class. The upper graph that, in general, the BarRef01 levels vary little compared to NoBarRef02 from 500 Hz through 6.3 kHz. Read the entire page →
From page 344... ... B - 183 Figure 170. Averages of the differences in Leq(5min) Read the entire page →
From page 345... ... B - 184 Downwind Lapse Class Figure 171 shows the results for the Downwind Lapse class. The results for these daytime periods are similar to those for the daytime Downwind Neutral class. Read the entire page →
From page 346... ... B - 185 Figure 171. Averages of the differences in Leq(5min) Read the entire page →
From page 347... ... B - 186 Calm Inversion Class Figure 172 shows the results for the Calm Inversion class. The results for these later evening periods are similar to those for the Calm Neutral class. Read the entire page →
From page 348... ... B - 187 Figure 172. Averages of the differences in Leq(5min) Read the entire page →
From page 349... ... B - 188 Comparison of Results for Downwind Lapse, Downwind Neutral, Calm Neutral and Calm Inversion at MD-5 For the MD-5 data, the results are shown by microphone pair. Keep in mind that the Downwind cases are in the afternoon measurement session and the Calm cases are in the evening session. Read the entire page →
From page 350... ... B - 189 Figure 173. Differences in the Calm Neutral average differences and Downwind Lapse, Downwind Neutral and Calm Inversion average differences (Leq(5min) Read the entire page →
From page 351... ... B - 190 Figure 174. Differences in the Calm Neutral average differences and Downwind Lapse, Downwind Neutral and Calm Inversion average differences (Leq(5min) Read the entire page →
From page 352... ... B - 191 Figure 175. Differences in the Calm Neutral average differences and Downwind Lapse, Downwind Neutral and Calm Inversion average differences (Leq(5min) Read the entire page →
From page 353... ... B - 192 Additional Sound Level Analysis – Ln Descriptors Figure 176 presents the L90(5min) Read the entire page →
From page 354... ... B - 193 Figure 176. Read the entire page →
From page 355... ... B - 194 Figure 178. Read the entire page →
From page 356... ... B - 195 Figure 180. Read the entire page →
From page 357... ... B - 196 The above graphs were for the broadband A-weighted sound levels and unweighted sound pressure levels. The next graphs broaden the analysis to include the individual 1/3 octave bands by use of color shading, where brown means that the Barrier levels are higher than the No Barrier levels and blue means that No Barrier levels are higher. Read the entire page →
From page 358... ... B - 197 Figure 183 presents the Ln differences for BarCom03 and NoBarCom05. Again, brown means Barrier levels are higher and blue means the No Barrier levels are higher. Read the entire page →
From page 359... ... B - 198 Figure 184 presents the Ln differences for BarCom04 and NoBarCom06. These results show increases in the BarCom03 levels relative to those for NoBarCom05 across most of the Ln descriptors in the bands centered on 100 through 160 Hz, which is some evidence of increases in sound pressure levels due to reflections off the barrier. Read the entire page →
From page 360... ... B - 199 Data Analysis for MD-5 - Spectrograms Refer to Table 14 for the MD-5 location six microphone positions. There are two equivalent microphones comparing a site with a barrier and one without: BarCom03 and NoBarCom05 and BarCom04 and NoBarCom06. Read the entire page →
From page 361... ... B - 200 Figure 185. MD-5 spectrograms for heavy truck on northbound (community) Read the entire page →
From page 362... ... B - 201 Figure 186. MD-5 spectrograms for a pickup truck on southbound (barrier) Read the entire page →
From page 363... ... B - 202 Figure 187. MD-5 spectrograms for Motorcycle on northbound (community) Read the entire page →
From page 364... ... B - 203 For this site, it is difficult to see a clear difference between the Barrier and the No Barrier sites since the traffic was not very dense. However, upon careful examination, it can be seen that hot spots are both wider and taller for a broad range of frequencies. Read the entire page →
From page 365... ... B - 204 Figure 188. MD-5 spectrograms for Forty-one minutes of clean data (no contamination from other noise sources) Read the entire page →
From page 366... ... B - 205 Data Analysis for MD-5 - Psychoacoustics Psychoacoustical Annoyance Metrics, Afternoon The results from the afternoon monitoring and the night monitoring at MD-5 were significantly different. This is most likely due to the large decrease in traffic volume at night compared to the daytime. Read the entire page →
From page 367... ... B - 206 BarCom04 36.4 3.8 0.14 -0.09 NoBarCom06 35.9 3.7 0.16 -0.51 Figure 190. Unbiased annoyance vs. Read the entire page →
From page 368... ... B - 207 Figure 191. Psychoacoustic annoyance vs. Read the entire page →
From page 369... ... B - 208 sound closer to ground level (level with the vehicles) , the annoyance metrics do not separate the Barrier and No Barrier cases effectively. Read the entire page →
From page 370... ... B - 209 BarCom04 3.75 0.96 0.95 2.77 NoBarCom06 4.50 0.92 0.42 1.57 CSA BarCom03 27.3 3.1 0.68 1.59 NoBarCom05 27.0 2.9 0.45 0.52 BarCom04 28.0 3.4 0.44 1.41 NoBarCom06 28.5 3.1 0.15 1.28 Figure 194. Unbiased annoyance vs. Read the entire page →
From page 371... ... B - 210 Figure 195. Psychoacoustic annoyance vs. Read the entire page →
From page 372... ... B - 211 C H A P T E R B - 8 Summary of Appendix B This Appendix presented the details of the research data collection and analysis protocols and the results at five studied single-barrier locations. The purpose of the measurements and analysis was to see if sound levels increased on the opposite side of the road from a noise barrier due to sound reflections off that barrier, and whether differences could be detected using spectrogram analysis or psychoacoustic metrics. Read the entire page →

From page 152...

... B - ii C O N T E N T S CHAPTER B-1 .................................................................................................................................. B-1 Introduction to Appendix B...................................................................................................................................