EPA 908/1 -81-001
STUDY OF SOUND LEVELS ALONG
THE RAILROAD RIGHT-OF-WAY
IN LITTLETON, COLORADO
U. S. ENVIRONMENTAL PROTECTION AGENCY REGION Vlil
Office of Noise and Radiation
Denver, Colorado 30295
March 1931
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EPA 908/1-81-001
STUDY OF SOUND LEVELS ALONG THE
RAILROAD RIGHT-OF-WAY
IN LITTLETON, COLORADO
by
RANDOLPH A. REEDER
U. S. Environmental Protection Agency Region VIII
Office of Noise and Radiation
Denver, Colorado 80295
March 1981
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DISCLAIMER
This report has been reviewed by the Office of Noise and Radiation,
Region VIII, of the U. S. Environmental Protection Agency and approved for
publication. Approval does not signify that the contents necessarily reflect
the views and policies of the U. S. Environmental Protection Agency, nor does
mention of trade names or commercial products constitute endorsement or
recommendation for use.
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CONTENTS
Pages
Acknowledgments iv
Definition of Noise Descriptors Used v
I. Introduction 1
II. Monitoring Sites 2
III. Equipment Used 10
IV. Sunmary of Data Obtained 11
V. Noise Levels With and Without Track Depression 14
VI. Conclusions 16
Append ix
A. Sound Level Data 19
B. Temperature Records 46
C. Calculation of Barrier Attenuation 48
i ii
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ACKNOWLEDGMENTS
The author is grateful to the following people for their assis-
tance in preparing this study: Lome York, Larry Svoboda, William
Bryan, and Kathryn Boone of the Environmental Protection Agency, Region
VIII, Office of Noise and Radiation; Dr. James Foch of the Region VIII
Noise Technical Assistance Center; Waldo Barton and Nancy Max Dost of
the Colorado Department of Highways.
iv
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DEFINITIONS OF NOISE DESCRIPTORS USED
La
The instantaneous sound level expressed in decibels (dB). This is
equal to the A-weighted sound pressure level referred to a reference
pressure of 20yPa = 2 x 10"5 N/m^
The sound exceedance level. This is the sound level which is
exceeded x% of the time.
Lmax
Lgq(T)
The maximum sound level obtained in some period of interest (lmax =
L0).
The equivalent (energy average) sound level for the time period T.
L (T) = 10 log-
A 0.1 L.(t)
I / 10
-eq«' -- --J10
In practice, leq(T) is calculated by the formula
Le, = 10 lo9l0
where is the sound level of
i n 0.1 L.
i C 10
_ 1=1
the i-th event, out of a total of n events all of equal time
intervals during the period T.
Ldn The day-night sound level. This is equal to a modified Leq for
24 hours with 10 dB(A) being added to all levels measured between
10 p.m. and 7 a.m.
Ld„ - 10 log
10
, ( /-2200 0.1 L.(t) /-0700 0.1 L.(t) + 1 )"
1 (/ 10 M dt +/ 10 M dt)
24 h
0700
2200
)
which is equivalent to
10 log1(J
' , (15 °-1 Ld, 9
^(Cio ^ 10 C
(i=l
j=l
°-1 Ln.r
J)
)
where is the hourly
L for the i-th hour of the day and L is the hourly L for the
eq n. eq
j-th hour of the night.
v
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I. INTRODUCTION
In May of 1980, the Noise Control Program of the U. S. Environmental
Protection Agency (EPA) Region VIII was requested by the Colorado State
Department of Highways to provide assistance in monitoring sound levels along
the railroad right-of-way through the City of Littleton, Colorado. The
Colorado Division of Highways, District 6 office, consulted with the Region
VIII Noise Program, and it was agreed that EPA noise monitoring equipment and
personnel would be used to obtain baseline sound levels along a section of the
Atchison, Topeka and Santa Fe and the Denver and Rio Grande Western Rail-
roads running through the City of Littleton. These baseline levels were to be
used for an environmental evaluation prior to the possible construction of a
railroad depression extending from a point south of Belleview Avenue to an
area near Ridge Road. The South Santa Fe Joint Development Environmental
Impact Statement will use the noise conditions found to predict future noise
levels from either a depressed or elevated railroad alternative.
The purpose of depressing the tracks would be twofold, to facilitate the
movement of motor vehicle traffic on such streets as Main, Alamo, and Prince
which cross the railroad right-of-way and to reduce the noise level of the
train traffic in the surrounding commnercial and residential area. The depth
of the depression will gradually increase south of Belleview to a maximum of
7.0 m (26 feet) deep at its midpoint where Main Steet will cross over the
depressed tracks and then decrease back to normal ground level near Ridge
Road. See illustration in figure 6.
Four sites were agreed upon from which to conduct the noise level sur-
vey. These were the Colorado Highway Maintenance Yard at West Chenango Avenue
and Rio Grande Avenue, the City of Littleton Police Department parking lot at
West Berry Avenue and South Rio Grande, the Littleton Fire Station at Main
Street and Rio Grande Avenue, and the parking lot of the auto mechanics shop
of Arapahoe Community College at West Lake Avenue and South Nevada Street.
These sites were chosen because of their nearness to the railroad right-of-
way, and they offered some security for the equipment which monitored noise
levels at night.
During the course of the monitoring, the opportunity was taken to check
compliance with the Railroad Noise Emission Standards promulgated by EPA.
These regulations state that locomotives manufactured after December 31, 1979,
shall not exceed an A-weighted sound level of 96 dB(A) measured at 30 meters
under any moving condition. See Title 40, Code of Federal Regulations, Chapter
I, Part 201, 41 FR 2184, January 14, 1976; amended by 45 FR 1252, January 4,
1980. The site clearance requirement for locomotive and railcar passby tests
(section 201.23 of this regulation) was adhered to as closely as possible.
However, since the site clearance requirement calls for a clear area approxi-
mately 60 meters by 90 meters, the clearance requirement was not met at every
monitoring site.
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- 2 -
The railroads involved in the study were notified of our intentions and
were requested to supply information about the number of trains, exact times
of pass-through, types of trains, and other information which would be helpful
in analyzing the sound level data. Some of this information was eventually
supplied to the EPA.
The monitoring program was delayed until August due to the time needed
to calibrate all necessary equipment and the fact that the Denver and Rio
Grande Railroad was in the process of upgrading and reballasting its tracks
throughout the monitoring area.
II. MONITORING SITES
All the sites which were used to monitor sound levels from train passbys
were located just west of the railroad right-of-way. Microphone positions
were located, inasmuch as conditions would allow, at 30 m (100 feet) as meas-
ured from the center line of the Denver and Rio Grande Western Railroad tracks
and at a height of between 1.2 m and 1.5 m above the ground. The distance
from the microphone position to the Santa Fe tracks was also measured and
varied from 61.3 m to about 77.1 m.
Each site was monitored for 2 days at a time. Measurements were made
consecutively at each site starting from the northernmost and going south.
Measurements of individual train passbys were made to obtain Lmax and Leq
values for the time of passby. Also, exceedance levels and Ldn were measured
using an integrating sound level analyzer which monitored levels during peri-
ods of 24 hours. Sites were monitored during the day by EPA personnel and in
the evenings by personnel of the Division of Highways.
Weather conditions during the monitoring period were good being warm and
dry a majority of the time. It was observed that all southbound trains used
the near tracks (the D&RGW tracks) and that all northbound trains used the far
tracks (the AT&SF tracks).
Site No. 1
This site was located inside the Colorado Highway Department's mainten-
ance yard at West Chenango Avenue and South Rio Grande Avenue as shown on the
aerial view in figure 1. Microphone positions were just east of the mainten-
ance building and 30.5 m from the near tracks and 70.4 m from the far tracks
as shown in the photograph of figure la. This site is just north of the
Belleview Avenue grade separation where the proposed depression would start
and the tracks here will not be affected by the project. This site will thus
provide a good reference for measurements after the completion of the pro-
ject. This site was monitored from the morning of August 4 until the morning
of August 6, 1980. Noise sources other than trains included motor vehicle
traffic on South Santa Fe Drive and heavy equipment operated in the mainten-
ance yard.
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- 3 -
Site No. 2
This site was located at the parking lot of the Littleton Center at West
Berry Avenue and South Rio Grande Avenue as shown on the aerial view of
figure 2. Microphone positions were on a grassy fringe facing Rio Grande
Avenue and the tracks as shown in the photograph of figure 2a. Near tracks
were at 35.1 m and the far tracks at 77.1 m. This site was monitored from the
afternoon of August 6 to the morning of August 8, 1980. Noise sources other
than trains included vehicle traffic along Rio Grande Avenue which amounted to
about 150 cars per hour total for both ways during the day.
Site No. 3
This site was located in the front parking area of the Littleton Fire
Station near the intersection of Main Street and Rio Grande Avenue and is
shown on the aerial view of figure 3. Microphone positions were in a parking
area facing Rio Grande Avenue at 29.0 m from the near tracks and 7.6 m from
the fire station building shown in the photograph of figure 3a. The far
tracks were blocked from direct view by the Littleton Railroad Station. This
site was monitored from the afternoon of August 8 to the afternoon of August
11, 1980, excluding Sunday, August 10. Other sources of noise included vehi-
cle traffic on both Main Street and Rio Grande Avenue and emergency vehicle
sirens at the fire station.
Site No. 4
This site was located in the parking area in front of the automotive
shops of the Arapahoe Community College at South Nevada Street and about West
Lake Avenue as shown in figure 4. Microphone positions were located in the
parking area about 14 m east of the building, 30.5 m from the near tracks and
61.3 m from the far tracks. This site is shown in the photograph in figure 4a
and was monitored from the morning of August 12 until the morning of
August 14, 1980.
Site No. 5
This site was located near the parking area of the City of Littleton
Police Department along Rio Grande Avenue and just north of Crestline Avenue
as shown on figure 2. Microphone positions were 36.6 m from the near tracks
across Rio Grande Avenue. This site was monitored by the Division of Highways
on the evenings of August 4 and 5, 1980.
Site No. 6
This site was located near the tennis courts at Arapahoe Community
College. Two microphone locations were used. The first was south of Aberdeen
Avenue about 30 m from tne near track. The microphone was then moved to a
second location north of Aberdeen in a parking lot as shown in figure 4. This
site was monitored by the Division of Highways on the evening of August 7,
1980.
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IMS
4
I
mSa-
M. Chenago Ave
V
t
Littleton, Colorado
I
«'>i A -
v-~. •
x-a .r
I
i
!
Figure 1. Aerial view of Site No. 1
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T ?
it 2 \
• 8 11
¦ III
u>
Sites No. 2 & 5
j Littleton, Colorado
Berry Ave.
i Site No. 2
Microphones
I
Littleton
Center
I
Crestline Ave
.7/ /if/i 177r("T| "( "¦ ---*v
v • w»»tv». wu v<» « *. ~-V
ms&s:
t '3 Site No. 5
rsBzr'f'ti ;tj,
• Microphone
7/
ihwmwnnh.i,;,
^ , KV X' ^ ;
=c , . Jx]
Tt « J
.... t > . v_., r
'ii #'' i t n 'H
: w> ' * ¦< v *. -i -n* i
• miiSL r - t M » '¦
a Li
Jf
; •¦«.' i j
i
£
Figure 2. Aerial view of Sites No. 2 and No. 5
-------
Figure la. Looking from tracks onto Site No. 1
Figure 2a. Looking from tracks onto Site No. 2
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Littleton. Colorado
W. Alamo St.
* " "
w.
I 9 ''UT-fi "2*
' , if J
f I
w. Littleton Blvd.
1
Main St. a"~"
H?r«41:
Arapahoe County
Court House
Microphones
f r » -
Littleton
Station
Littleton
Fire Station
4«'«-!
Figure 3. Aerial view of Site No. 3
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Sites No.
Littleton, Colorado
V
Cemetery
m
Scale:
cm = 24 m
r
crophones
Arapahoe
Commun
W. Aberdeen Ave. r
crophone
I*!^ «5 -« -* ^ ii'5
ai III g II ^ ii s
Figure 4. Aerial view of Sites No. 4 and No. 6
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Figure 3a. Looking from tracks onto Site No. 3
Figure 4a. Looking from tracks onto Site No. 4
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III. EQUIPMENT USED
Sound levels were measured at the different sites by using four separate
monitoring systems. All equipment used in this study was fully tested and
calibrated to tolerances set by the American National Standards Institute
(ANSI) by the manufacturer or an independent acoustic testing company using
standards traceable to the National Bureau of Standards within a year prior to
the study period.
The first system measured instantaneous (sampling rate of 0.125 of a
second) sound levels from which were obtained an Lmax for locomotive passbys
and an average railcar passby sound level. This system consisted of a GenRad
1981-B Precision Sound-Level Meter (EPA No. 123345 and 123346) used in con-
junction with a GenRad 1985 DC Strip Chart Recorder (EPA No. 123343 and
123342). Two of these systems were used simultaneously during the EPA's day-
time measurements to insure that no train passby would be missed. These
instruments have a dynamic range of from 30 to 120 dB(A) (A-weighted) and meet
the ANSI specifications for a type S1A meter. Each system was calibrated by
using a GenRad model 1567 Sound Level Calibrator (112.8 dB(A) at 1,000 Hz)
before and after the measurement period.
The second system consisted of a GenRad 1933 Precision Sound-Level Meter
and Analyzer which acted as an input to the Kudelski model Nagra IV-SJ
Scientific Tape Recorder and to the Digital Acoustic model DA 607P v.02
Community Noise Monitor. The 1933 was set on flat and fast response and all
train passbys were recorded on tape for later analysis. The DA 607P was set
on A-weighting and fast response and measured hourly Leq's during EPA's
daytime monitoring.
The 1933 (EPA No. 115973) meets ANSI specifications for a type 1 sound-
level meter and has a measurement range of from 22 to 130 dB(A) using the
1-inch microphone. It was calibrated with a GenRad model 1562-A Sound-Level
Calibrator before and after each measurement period.
The Nagra IV-SJ (EPA No. 115756) is a 3-track tape recorder with an
instrument frequency response of + 1.5 dB(A) between 25 Hz and 10 kHz. The
primary recording channel, No. 1, was set so as just not to saturate the tape
during calibration (112.8 dB(A)). Channel No. 2 was attenuated 10 dB(A)
higher relative to channel No. 1 in order to record sounds significantly
higher which would saturate channel No. 1. Tapes obtained with this equipment
were later analyzed using the DA 607P to obtain Lmax and Lpn for the time
of the train passby. 6Q
The DA 607P Community Noise Monitor (EPA No. 123361) is a type 1 sound-
level meter and analyzer which samples eight times a second with a resolution
of 0.1 dB(A). Its dynamic range is typically 26 to 140 d8(A) with a frequency
response of +.25 to -1.5 dB(A) over the range 10 Hz to 20 kHz. It produces a
permanent record of sound levels monitored using such descriptors as Leq,
- 10 -
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- 11 -
Lmax> Lmin, exceedance levels, interval mean and standard deviations, bar
histograms of data and so on over a period of time determined by the opera-
tor. This instrument was used to measure Leq (1 hour) during daytime moni-
toring and later analyze tapes of individual train passbys.
The third system used to monitor sound levels was the GenRad model 1945
Community Noise Analyzer (EPA No. 116109) with the GenRad Weatherproof Mike
System and Weatherproof Enclosure. This instrument has a dynamic range of
from 25 to 120 dB(A) (A-weighted) and is calibrated using a GenRad model
1562-A Sound-Level Calibrator. The 1945 was set into its weatherproof enclo-
sure and chained to some local post and left overnight to measure L(jn and
exceedance levels over a 24-hour period.
The fourth system was used by the Colorado Division of Highways and
consisted of a Quest model 228 Integrating Sound-Level Meter used in conjunc-
tion with a Quest model 142 Graphic Chart Recorder. This instrument was used
to measure Leq for train passbys during the evenings.
Wind speed and direction were measured during the daytime monitoring
period by use of Weathertronics model 2361 Recording Wind System (EPA No.
123319). Winds were never observed to exceed 16 km/h during the daytime moni-
toring periods. Temperature measurements were also made during the same time
period and are given in the appendix B.
IV. SUMMARY OF DATA OBTAINED
A complete record of the sound level data obtained from each monitoring
site is included in appendix A of this report. It should be noted that all
trains observed were in compliance with EPA regulations on railroad noise
emission standards which set a maximum level of 96 dB(A) for locomotives under
moving conditions and 88 dB(A) for railcars moving with speeds up to and
including 72.4 km/h as measured with fast meter response at a distance of 30 m
(100 feet) from the centerline of the track and with the microphone at 1.2 m
(4 feet) above ground level. These provisions do not apply to warning
devices, such as horns and whistles when operated for the purpose of safety.
Noise from whistles was measured to be as much as 10 dB(A) higher than the
sound of the locomotive passby without whistles.
From data supplied from the railroads, an average number of 13.6 trains
per day southbound (on near tracks) was obtained and an average of 13.1 trains
per day northbound (on far tracks) was obtained to give an average over the
11-day observing period of 27 trains per day both ways.
At site No. 1, the average Lmax for trains on the near tracks was
86.7 dB(A) while the arithmetic average Lmax for trains on the far tracks
was 72.4 dB(A), a difference of 14.3 d8(A). Similarly, at site No. 4, the
average Lmax for trains on the near tracks was, discounting noise from
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- 12 -
whistles, 90.3 dB(A) while the average lmax for trains on the far tracks was
74.0 dB(A), a difference of 16.3 dB(A). This difference cannot be explained
by the fact that the far tracks were about twice as far away from the micro-
phone position as were the near tracks. This distance difference should,
everything else being equal, only result in a 7 or 8 dB(A) decrease in the
maximum sound levels coming from the train passbys. This difference in levels
may be due to the fact that southbound trains face a slight uphill grade and
are expending more power than northbound trains. Also, it was noted that all
coal trains were full going south, many times with six engines pulling and two
engines pushing, while all coal trains going north were empty with no engines
pushing. This difference in sound levels from near and far trains implies
that those trains on the near tracks were the significant source of railroad
noise (excluding whistle noise) which contributed to the measured Lea's and
Ldn's.
The arithmetic average of the differences between maximum locomotive
sound levels and average railcar sound levels was calculated to be 15.7 d8(A).
This was found using 10 pieces of data from all sites for those trains on the
near tracks long enough to give reliable levels for the railcars.
The loudest noise recorded from a locomotive at 30 m was from a coal
train on the near tracks which gave a 95.1 dB(A) reading. Another coal train
at 28 m gave a reading of 106.9 dB(A) from whistle noise which was the loudest
sound recorded during the entire monitoring period.
The average Lmax for coal trains on the near tracks was 92.6 dB(A)
calculated from six pieces of data and the arithmetic average Lmax f°r
freight trains on the near tracks was 86.9 dB(A) calculated from 12 pieces of
data, a difference of 5.7 dB(A). This indicates that sounds from southbound
(full) coal trains have at least three times the intensity on the average as
sounds from southbound freight trains.
Tables 1 and 2 gives a sunmary of the and average hourly Leq
data recorded at all the sites. The measured L,jn does not show a direct
correlation with the total number of trains that went by on the near tracks
(as supplied by the railroads) during the measurement period. The near track
passby of these trains was assumed to be the predominant source of noise at
the locations monitored. The average Leq (1 hour), when used to estimate
the measured L^n by the formula
r 105 '"eq^~l
Ldn = 10 log^g —10 M , gave values for l_dn which are from
6.3 dB(A) to 0.8 dB(A) lower than the actual measured values. Thus, the aver-
age Leq(l) obtained from daytime monitoring was probably not quite a suffi-
cient indicator of the true average Len(l). The average value of Ldn
calculated from all sites measured is 73 dB(A) and the average Leq (1 hour)
is 63.5 dB(A).
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te
1
1
2
2
3
te
4
4
4
4
4
- 13 -
Table 1
Measured
Average
Per i od
Ldn
Leq (1 hour)
10:41, 8/04/80
to
10:41, 8/05/80
69
56.3
11:15, 8/05/80
to
11:15, 8/06/80
70
62.4
11:45, 8/06/80
to
11:45, 8/07/80
71
63.5
11:55, 8/07/80
to
11:55, 8/08/80
72
61.1
09:15, 8/11/80
to
09:15, 8/12/80
80
70.7
Number of trains
On near track
14
13
12
15
11
Period
09:45, 8/12/80
to
17:45, 8/12/80
17:45, 8/12/80
to
01:45, 8/13/80
01:45, 8/13/80
to
09:45, 8/13/80
09:45, 8/12/80
to
09:45, 8/13/80
10:00, 8/13/80
to
10:00, 8/14/80
Average
L6£ (1 hour)
l-dn = 74
63.6
Table 2
Measured
J^eg
Leq (8) =69
Leq (8) = 69
leq (8) =68
L(jn (calculated)
= 75 63.6
66.8
Number of
trains on
near track
15
1 8
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V. NOISE LEVELS WITH AND WITHOUT TRACK DEPRESSION
In this section, predictions are made of the sound levels which will be
experienced at the railroad right-of-way boundary by the three alternatives
studied in the Santa Fe Joint Development Corridor EIS using data supplied by
the Division of Highways on November 12 and December 1, 1980. These alterna-
tives include leaving the existing alignment as is, elevating the tracks, or
depressing the tracks. Leaving the existing tracks as they are or elevating
the tracks will not change the noise levels measured provided that rail traf-
fic does not increase. Depressing the tracks may lower noise levels at the
right-of-way boundaries from present levels due to barrier attenuation depend-
ing on the exact location in the development area.
Since measurements were obtained at 30 m from train passbys, to calcu-
lated levels at the right-of-way boundaries which vary from place to place
along the route, one uses the forumula
L = Lref " 20 10910 (d^f) where L is the A-weighted sound level at the position
of interest d, and Lrpf is the level measured at the reference distance
dref (30 m in our case). This formula is good for attenuation of sound due
to divergence from a nondirectional point source and will be used to approxi-
mate levels from locomotives. The formula gives a 6 dB(A) attenuation for each
doubling of the distance from the source.
For levels from railcars of long trains (greater than 10 cars), the
formula L = L^ - 10 log^g ^ ^ | for the level at the position d is used.
This formula is valid for a very long line source of sound and gives a 3 dB(A)
attenuation for each doubling of the distance from the source.
These formulas provide fairly good results in homogeneous atmospheres
with no wind for distances less than 300 m (1,000 feet) from the source. For
distances greater than this, attenuation by atmospheric absorption should be
included in any calculation.
Calculation of barrier attenuation was done using the Mackawa barrier
attenuation formula for Fresnel diffraction from a rigid barrier. To use the
formula, an octave-band analysis of a typical coal train was performed and
separate calculations were done for locomotive and railcar sound levels with
given distances from the source and a receiver. The details of this procedure
are given in appendix C.
In calculating the projected noise levels, the Lmax and Ldn, at the
right-of-way lines for the various alternatives, it is assumed that the major
source of noise is the exhaust from the locomotive on the track nearest to the
right-of-way line. Noise from the railcars is some 15 dB(A) below locomotive
- 14 -
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- 15 -
noise on the average, and thus does not contribute significantly to the pro-
jected L(jn.
For the elevated alternative the distance from the Rio Grande track to
the western right-of-way line will vary between 39.6 m amd 51.8 m. There is
no proposed barrier along this route (see figure 5). At the right-of-way
distance of 39.6 m, the cut slope will block the line-of-sight to the tracks
for an observer on the ground and so provide some slight attenuation of rail-
car noise. However, it will not provide any attenuation for a noise source
located 4.6 m about the tracks as is a locomotive exhaust. Thus, the Lmax
for an average coal train using an Lref of 92.6 dB(A) at 30.5 m will vary
from 90.3 dB(A) (at 39.6 m) to 87.9 dB(A) (at 51.8 m). The Lmax for an
average freight train (reference 86.9 dB(A) at 30.5 m) will be between
84.6 dB(A) and 82.3 dB(A) at the right-of-way boundary. The distance from the
Sante Fe track to the eastern right-of-way line will vary from 15.2 m to
65.8 m. The lmax for an average coal train will then be between 98.6 dB(A)
to 85.9 dB(A). The Lmax for an average freight train will be between
92.9 dB(A) to 80.2 dB(A).
For the depresssed alternative, the distance from the Rio Grande track to
the western right-of-way is again between 39.6 m and 51.8 m. Since there is
no proposed barrier along this side, the Lmax levels for the average coal
train again vary between 90.3 and 87.9 dB(A], and the Lmax for the average
freight train will vary between 84.6 dB(A) to 82.3 dB(A).
Along the eastern side, a barrier is proposed at a distance of 11 m from
the Santa Fe tracks. This will provide an attenuation at the eastern right-
of-way boundary line. Assuming this barrier is 7.3 m in height from the top
of the rails, the Lmax from locomotive noise is calculated to be for an
average coal train 89 dB(A) at the near right-of-way boundary of 4.3 m and
73.4 dB(A) at 54.9 m from the barrier. A difference of 9.6 and 12.5 dB(A)
respectively from those values without the barrier present. For the average
freight train the Lmax is found to be from 83.3 dB(A) to 67.7 dB(A).
For the case of railcars, assuming a long train and an average difference
of 15.7 dB(A) between locomotive levels and railcar levels, the attenuation at
4.3 m from the barrier results in a level of 67 dB(A) for coal train cars and
61.3 dB(A) for freight train cars. At 54.9 m from the barrier, the results
are 57.8 dB(A) for the coal train and 52.1 dB(A) for the freight train. This
is equivalent to a difference of 12.5 dB(A) from the value at 4.3 m without
the barrier and a difference of 15.7 dB(A) from the value at 54.9 m without
the barrier.
Predictions for the at the right-of-way boundaries for existing and
future (year 2000) rail traffic are given in table 3. These values were cal-
culated using the average measured L(jn at 30 m of 73 dB(A) as the reference
value with an average total of 14 trains per day one way through the study
area. The L
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- 16 -
Table 3
1981 Ldn 200U Ldn
A1ignment dB(A) dB(A)
Existing
Track at 12.2 m from east right-of-way 81 85
Track at 48.4 m from east right-of-way 69 73
Elevated
Track
at
15.2
m
from east right-of-way
79
83
Track
at
65.8
m
from east right-of-way
66
70
Track
at
39.6
m
from west right-of-way
71
75
Track
at
51.8
m
from west right-of-way
68
72
Depressed
Track
at
15.2
m
from east right-of-way
71*
75*
Track
at
65.8
m
from east right-of-way
58*
62*
Track
at
39.6
m
from west right-of-way
71
75
Track
at
51.8
m
from west right-of-way
68
72
*The values assume a 7.3 m high barrier wall.
CONCLUSIONS
The sound levels obtained as a result of this study indicate that rail-
road sounds are probably the major source of noise in the areas monitored. An
average L,jn of 73 dB(A) at 30 m is very intense for an outdoor area,
although this level was recorded inside the railroad right-of-way boundary.
The EPA's regulations for moving trains were not observed to be violated;
however, the levels recorded in the study area are clearly above the EPA
recommended noise levels of = 55 dB(A) for outdoor residential areas and
other areas where people spend limited amounts of time.
Of the alternative proposals provided by the Division of Highways, only
the depressed alternative offers any reduction of noise levels from their
present values. The only substantial reduction will occur in those areas
where the height of the retaining wall is 4.6 m or more above the bed of the
rail tracks so as to shield observers from the top of locomotive engines which
are the major sources of sound during train passbys. This would result in an
average 8 dB(A) reduction of the L
-------
Looking North
cmtTiN
UIT
a* m.
mo 9ranoc
TRACK
i
SANTA FE
TRACK
f KltTINO
I AST
a aw
LINE
99 O* ~ ISO 0'
40 0' - 190 0'
/
RAILROAD/TRANSIT CORRIDOR
EXISTING ALIGNMENT
i i t
RIO 9RANDC FUTURE SANTA FC
TRACK TRACK TRACK
IKI9TIM9
90 0
39 0'
19 O - TO 0'
SERVICE
SERVICE
ROA 0
RAILRO AO/TRANSIT CORRIDOR
ELEVATED ALTERNATIVE
9 0' 39 0* 19 <7
so O
14 0 * 190 0'
IXI9TIN9 WEST
ROW LINE
tit
RIO 9RAN0C FUTURE SANTA FE
TRACK TRACK TRACK
EXI9TIN0
COMM
LINE
LINE
SERVICE
SERVICE
ROA 0
RAIL ROA 0/TRANSIT CORRIDOR
OEPflESSEO ALTERNATIVE
l '« ¦ " "v ¦- ——*¦
•ANTA FE JOINT
OCVCLOPMCNT CORRIOOR
ROUTE ALIGNMENT ALTERNATIVES
BELLEVIEW AVENUE TO RIOOE ROAD
-------
!f#V
r"f a
FIGURE 6
AERIAL OBLIQUE SKETCH OF PROJECT
-------
APPENDIX A
SOUND LEVEL DATA
-------
Date: 8/04/80
Train
Number Time
1 11:05
2 11:50
3 12.18
4 13.05
5 13.20
6 13:45
7 14.23
8 14.45
9 14.55
Site: No. 1
Type Track
freight near
coal near
engines far
coal far
coal near
freight far
freight near
freight far
freight far
Number of
Engines
3
6 + 2
4
6
6 + 2
2
2
5
1
Near tracks at: 30.5 m Far tracks at: 70.4 m
Lmax
Engines
1985 Record Tape
Number Lave Leq
of Cars Cars (1985) (time)
over range 88.1 57 68 76.6
(2 min 56
86 87.9 110 75 77.6
(4 min 16
over range 83.3 - - 79.0
(15 s)
74 72.9 110 63 63.7
(3 min 29
over range 91.5 103 77 80.6
(3 min 16
66 65.4 8 - 61.1
(30 s)
78 77.7 8 - 71.9
(44 s)
83 84.9 46 65 73.9
(2 min 25
68 66.9 10 - 60.7
(50 s)
w = whistle
-20-
-------
Date: 8/05/80
Site: No. 1
Train Number of
Number Time Type Track Engines
1 10:11 engines far 2
2 12:00 freight near 4
3 12:07 freight far 1
4 12:16 freight near 1
5 12:58 freight far 1
6 14:30 freight far 1
Near tracks at: 30.5 m Far tracks at: 70.4 m
L,
max
Engines Lmax Number Layp Uq
1985 Record Tape of Cars Cars (1985) (time)
73 71.9 - - 67.6
(7 s)
93 104.3 85 80 85.6
(w) (2 min 42
65 65.5 9 - 61.3
(20 s)
79 81.9 15 - 75.6
(53 s)
66 68.3 11 - 64.1
(31 s)
(not obtained due to 16 - (rain)
rain)
w = whistle
-21-
-------
Date: 8/06/80
Site: No. 2
Train
Number Time
1 12:06
2 12:38
3 14:00
4 14:27
Type Track
freight near
freight near
coal far
freight far
Number of
Engines
5 + 1
1
3
1
5
14:36 coal
far
3
Near tracks at: 35.1 m
Far tracks at: 77.1 m
Lmax
Engines Lmax Number Layp Len
1985 Record Tape of Cars Cars (1985) (time)
84 85.5 92 75 77.2
(3 min 37
82 85.3 12 - 77.3
(1 min 8 s
79 78.7 70 68 66.5
(2 min 14
67 68.6 11 - 64.8
(43 s)
66 (autos 105 64 66.6
in way) (49 s)
w = whistle
-22-
-------
Date: 8/07/80
Site: No. 2
Train
Number Time
1 09:53
2 12:59
3 13:40
4 13:50
5 14:37
6 15:00
Type Track
coal far
freight far
freight far
coal far
coal far
freight far
Number of
Engines
4
1
7
4
2
3
Near tracks at: 35.1 m
Far tracks at: 77.1 m
Lmax
Engines
1985 Record
•-max Number La»p Leq
Tape of Cars Cars (1985) (time)
76 (not on 116 60
tape)
(did not pass by) 2 (did not pass by)
75 78.7 95 60 66.4
(auto) (3 min 34 s)
66 72.4 110 55 61.1
(auto) (6 min 7 s)
67 69.8 67 55 65.1
(41 s)
74 (not on 85 55
tape)
w = whistle
-23-
-------
Date: 8/08/80
Site: No. 2
Train
Number Time
1 09:30
2 10:44
3 11:31
4 11:40
Type Track
coal near
freight far
freight far
freight near
Number of
Engines
6 + 2
3
2
1
Near tracks at: 35.1 m
Far tracks at: 77.1 m
Lmax
Engines Lmax Number Layp Leq
1985 Record Tape of Cars Cars (1985) (time)
92 (not on 110 75
tape)
75 76.0 89 60 66.9
(3 min)
76 77.2 39 - 69.1
(1 min 46 s
81 83.6 8 77.1
(auto) (39 s)
-24-
-------
Date: 8/08/80
Train
Number Time
5 13:17
6 13:33
7 14.20
Site: No. 3
Type Track
freight far
coal far
freight far
Number of
Engines
7
3
Near tracks at: 28.0 m Far tracks at: Blocked
from view
^max
Engines Number Layp Leq
1985 Record Tape of Cars Cars (1985) (time)
80 82.2 60 62 72.4
(2 min 22 s)
(over range) 77.5 (w) 111 55 65.4
(2 mm 13 s)
(over range) 80.0 (w) 10 62 67.4
(1 m 25 s)
w = whistle
-25-
-------
Date: 8/11/80
Site: No. 3
Train
Number Time
1 12:08
2 12:20
3 12:25
4 13:19
5 13:31
6 14:15
Type Track
engines far
freight near
freight far
freight near
coal near
freight far
Number of
Engines
2
1
1
4
3 + 1
1
Near tracks at: 28.0 m
Far tracks at: Blocked
from view
Lmax
Engines Lmax Number Layp Leq
1985 Record Tape of Cars Cars (1985) (time)
79 88.8 (w) - - 77.3
(25 s)
76 98.8 (w) 10 - 77.4
(did not pass by) (2 min 42 s)
(not recorded) 7 (not recorded)
87 101.5 (w) 55 75 88.1
(2 min 15 s)
94 106.9 (w) 75 77 93.9
(2 min 12 s)
82.9 (w) 8 - 68.5
(33 s)
w = whistle
-26-
-------
Date: 8/12/80
Train
Number Time
1 10:25
2 10:37
3 10:59
4 11:30
5 11:58
6 12:02
7 12:15
8 12:47
9 13:20
Site: No. 4
Number of
Type Track Engines
coal far 6
coal far 6
freight near 1
freight far 1
engine far 1
coal far 6
freight far 1
engines far 2
freight near 2
Near tracks at: 30.5 m
Far tracks at: 61.3 m
Lmax
Engines Lmax Number La„p Leq
1985 Record Tape of Cars Cars (1985) (time)
76 94.3 (w) 115 60 75.3
(3 min 38
67 93.5 (w) 110 56 71.2
(2 min 51
85 86.4 8 - 78.0
(27 s)
71 101.1 (w) 2 - 90.3
(21 s)
(not recorded) -
76 94.9 (w) 106 56 74.1
(3 min 13
70 90.6 (w) 8 - 81.9
(17 s)
100.5 (w) - - 92.0
(26 s)
89 92.8 62 76 82.0
(1 min 57
w = whistle
-27-
-------
Date: 8/13/80
Train
Number Time
1 10:04
2 10:55
3 11:21
4 11:38
5 11:51
6 12:28
7 13:05
8 13:19
9 13:37
10 14:00
Site: No. 4
Number of
Type Track Engines
coal near 6+2
freight far 2
coal far 6
freight near 1
freight far 3
freight far 1
engines far 2
freight far 1
coal near 6+2
freight near 1
Near tracks at: 30.5 m
Far tracks at: 61.3 m
l-max
Engines Lmax Number La„p Uq
1985 Record Tape of Cars Cars [1985) (time)
93 94.8 106 70 78.1
(4 min 3 s)
71 69.3 58 65
81 97.2 (w) 110 60 76.6
(3 min 50 s)
81 83.8 10 - 76.9
(42 s)
81 93.4 (w) 65 65 75.9
(2 min 35 s)
79 93.0 (w) 12 - 83.2
(32 sec)
96.5 (w) - - 86.2
(36 s)
70 96.7 (w) 11 - 84.7
(39 s)
94 95.1 114 74 84.6
(2 min 55 s)
87 89.2 7 - 83.7
(17 s)
w = whistle
-28-
-------
Date: 8/12/80
Train
Number Time
1 15:35
2 16:02
3 16.30
4 16:40
5 17:30
Site: No. 4
Number
of
Type Track Engines
freight near 4
engine far 1
freight near 2
engine near 1
freight near 4
Near tracks at: 30.5 m
Speed
Number Approx. Max Leq
of Cars (mph) LPg (4g) (time)
73 25 90.0 78.7
(4 min 16
20 81.2 72.1
(1 min 4 s
58 25 90.5 78.0
(4 min 16
20 68.1 57.3
(1 min 4 s
92 30 89.2 75.7
(4 min 16
-29-
-------
Date: 8/12/80
Train
Number Time
1 10:05
2 10:58
3 11.28
4 11:40
5 11:53
6 12:40
7 13:07
8 13.20
9 13:37
Site: No. 4
Number
of
Type Track Engines
coal near 6+2
freight far 2
coal far 6
freight near 1
freight far 3
freight far 1
engines far 2
freight far 1
coal near 6+2
Near tracks at: 30.5 m
Speed
Number Approx. Max Leq
of Cars (km/h) LPg (4C) (time)
106 40 92.0
62 40 79.1 78.8
(2 min 8
110 40 90.6 77.0
(4 min 16
10 40 84.0 74.9
(2 min 8
69 40 89.0 75.8
(4 min 16
12 40 92.5 82.5
(1 min 4
40 91.0 84.5
(1 min 4
11 40 91.0 83.5
(lmin 4 s
114 48 92.0 82.4
(4 min 16
-30-
-------
Date: 8/04/80
Site: No. 5
Number
Train of
Number Time Type Track Engines
1 19:50 coal near 6 + 2
2 22:25 coal near 6+2
3 11.20 freight near 4
4
11:30
engines
2
Near tracks at: 36.6 m
Speed
Number Approx. Max Leq
of Cars (km/h) LPg (4^) (time)
48 80.0 72.0
(4 min 32
48 79.2 70.0
(4 min 16
52 40 79.2 70.0
(4 min 16
56
-31-
-------
Date: 8/05/80
Train
Number Time
1 19:30
2 19:40
3 20:08
4 20:20
5 20:38
6 21:32
7 22:32
8 22.35
Site: No. 5
Number
of
Type Track Engines
coal near 6+2
engines far 2
coal near 6+2
freight near 2
engines far 2
freight near 3
freight far 2
coal far 6
Near tracks at: 36.6 m
Speed
Number Approx. Max Leq
of Cars (km/h) LPg (4c) (time)
48 90.0 81.0
(4 min 16
48 74.2 69.0
(1 min 4 s
48 89.8 81.0
(4 min 16
52 40 88.1 78.0
(4 min 16
32 67.2 61.0
(1 min 4 s
38 48 88.3 79.0
(2 min 8 s
66 40 79.0 65.0
(4 min 16
40 78.0 69.5
(4 min 16
-32-
-------
Date: 8/13/80
Site: No. 6
Number
Train of
Number Time Type Track Engines
1 18:40 freight far 3
2 18:45 engines far 2
3 19:16 freight far 2
4 19:35 freight near 2
5 21:45 background noise
6 22:25 freight near 4
7 23:20 coal near 6+2
Near tracks at: 30.5 m
Speed
Number Approx. Max Lpq
of Cars (km/h) LPq (4C) (time)
53 40 84.5 73.0
(2 min 8 s
40 74.5 68.5
(1 min 4 s
2 40 87.5 73.5
(4 min 16
35 48 88.2 80.0
(2 min 8 s
46.7
(2 min 8 s
89 56 88.5 73.2
(4 min 16
48 89.0 80.9
(4 min 16
-33-
-------
Site: No. 1
1945 Measurements for the period DA 607 P
10:41, 8/04/80 to
10:41, 8/05/80 24 hours Measurements of Leg
Exceedance Value Period LPg (1 hour)
Lmax 92 09:30 - 10:30, 8/05/80 56.3
Lo.l 87
Li 77
l_2 72
L5 63
Lio 59
L20 56
1-50 50
Lgo 41
L99 36
!-mi n ^6
Ldn
-34-
-------
Site: No. 1
1945 Measurements for the period DA 607 P
11:15, 8/05/80 to
11:15, 8/06/80 24 hours Measurements of Leg
Exceedance Value Perlod LPg (1 hour)
Lmax
103
10:30 -
11:30,
8/05/80
53.8
LO.1
88
11:30 -
12:30,
8/05/80
72.4
Ll
77
12:30 -
13:30,
8/05/80
63.1
1-2
73
13:30 -
14:30,
8/05/80
60.6
1-5
67
LlO
62
09:30 -
10:30,
8/06/80
62.1
1-20
57
1-50
51
1-90
43
L99
39
Lmi n
35
l-dn
70
-35-
-------
Site: No. 2
1945 Measurements for the period DA 607 P
11:45, 8/06/80 to
11:45, 8/07/80 24 hours Measurements of Leg
Exceedance Value Period Lpq (1 hour)
*-max
104
11:50
- 12:50,
8/06/80
70.6
Lo.l
87
12:50
- 13:35,
8/06/80
62.5
Ll
76
13:50
- 14:50,
8/06/80
63.4
1-2
73
l5
68
09:20
- 10:20,
8/07/80
60.7
LlO
63
10:20
- 11:20,
8/07/80
60.3
>-20
57
l50
50
L90
46
L99
44
^min
43
Ldn
71
-36-
-------
Site: No. 2
1945 Measurements for the period
11:55, 8/07/80 to
11:55, 8/08/80 24 hours
Exceedance
L-max
Lo.l
Ll
1-2
l5
Value
97
87
76
73
67
DA 607 P
Measurements of L
Per i od
eg
Lpg (1 hour)
11:20 - 12:20, 8/07/80 61.1
12:20 - 13:20, 8/07/80 58.7
13:20 - 14:20, 8/07/80 62.1
L10
62
09:35
- 10:05,
8/08/80
59.1
1-20
56
10:05
- 10:35,
8/08/80
62.5
L50
49
10:35
- 11:05,
8/08/80
62.1
1-90
46
11:05
- 11:35,
8/08/80
62.9
L99
44
Lmi n
42
Ldn
72
-37-
-------
1945 Measurements for the period
12:20, 8/08/80 to
12:20, 8/09/80 24 hours
Exceedance Value
Lmax
106
L0.1
93
Ll
77
L2
73
l5
67
LlO
63
l20
59
L50
53
l90
42
L99
37
Lmin
35
^dn
110
do not believe!
Site: No. 3
DA 607 P
Measurements of Leg
Per i od
Lpq
(1/2 hour)
12:32
- 13:02,
8/08/80
64.3
13:02
- 13:32,
8/08/80
65.5
13:32
- 14:02,
8/08/80
65.6
14:02
- 14:32,
8/08/80
64.1
14:32
- 15:02,
8/08/80
62.9
15:02
- 14:32,
8/08/80
64.7
-38-
-------
Site: No. 3
1945 Measurements for the period
09:15, 8/11/80 to
09:15, 8/12/80 24 hours
Exceedance Value
t-max
107
L0.1
95
Ll
78
^2
74
l5
68
1-10
64
1-20
60
l50
53
1-90
42
L99
39
1-mi n
37
1-dn
80
DA 607 P
Measurements of Leg
Period LPg (1 hour)
09:39 -
10:39, 8/11/80
60.1
10:39 -
11:39, 8/11/80
64.6
11:39 -
12:39, 8/11/80
70.4
12:39 -
13:39, 8/11/80
81.4
13:39 -
14:39, 8/11/80
76.9
-39-
-------
Site: No. 4
1945 Measurements for the period DA 607 P
09:45, 8/12/80 to
17:45, 8/12/80 8 hours Measurements of Leg
Exceedance Value Period LPq (1 hour)
Lmax
104
10:04 -
11:04,
8/12/80
65.3
•-0.1
92
11:04 -
12:04,
8/12/80
68.9
Ll
78
12:04 -
13:04,
8/12/80
70.9
1-2
74
13:04 -
14:04,
8/12/80
66.7
>-5
61
14:04 -
15:04,
8/12/80
46.4
LlO
55
1-20
50
1-50
46
>-90
43
L99
41
l-min
39
Leq (8 h)
69
-40-
-------
Site: No. 4
1945 Measurements for the period DA 607 P
17:45, 8/12/80 to
01:45, 8/12/80 8 hours Measurements of Leg
Exceedance Value Period LPg (1 hour)
Lmax 98
LO.I 92
Li 79
L2 74
l_5 66
LlO 56
L20 50
L50 45
L90 46
L99 44
Lmin ^3
Leq (8h) 69
-41-
-------
Site: No. 4
1945 Measurements for the period DA 607 P
01:45, 8/13/80 to
09:45, 8/13/80 8 hours Measurements of Leg
Exceedance Value Period LPg (1 hour)
Lmax 96
L0.1 91
Li 80
L2 74
L5 62
LlO 56
L20 52
L50 47
Lgo 44
L99 43
'-min 41
Leq (8h) 68
-42-
-------
Site: No. 4
1945 Measurements for the period
10:00, 8/13/80 to
10:00, 8/14/80 24 hours
Exceedance
LlO
L20
L50
L90
L99
'-min
l-dn
Value
56
50
46
42
41
40
74
DA 607 P
Measurements of L
Per i od
eg
LPg (1 hour)
Lmax
98
09:46
- 10:46,
8/13/80
66.5
L0.1
91
10:46
- 11:46,
8/13/80
66.5
Ll
78
11:46
- 12:46,
8/13/80
65.5
l2
72
12:46
- 13:46,
8/13/80
73.3
l5
63
13:46
- 14:46,
8/13/80
62.3
-43-
-------
APPENDIX B
Temperature Records
-------
Record of Temperature Measurements
Date: 8/04/80
Time
12:00
13:30
14:20
Site No. 1
Temperature °C
28
29
31
Date 8/05/80
Time
09:30
12:30
13:30
Site No. 1
Temperature °C
28
30
31
8/06/80
Site No. 1
Date: 8/06/80
Site No
Time
Temperature °C
Time
Temperature °C
10:00
29
12:00
33
11:00
32
13:00
36
14:00
37
15:00
38
-45-
-------
Record of Temperature Measurements
8/07/80
Site No. 2
Date 8/08/80
Site No. i
Time
Temperature °C
Time
Temperature °C
9:30
29
09:30 '
20
10:30
32
11:30
33
12:30
34
13:30
35
14:30
36
8/08/80
Site No. 3
Date: 8/11/80
Site No. :
Time
Temperature °C
Time
Temperature °C
13:30
27
10:00
26
14:30
27
11:00
27
12:30
29
13:30
31
14:30
32
-46-
-------
Record of Temperature Measurements
Date: 8/12/80 Site No. 4 Date 8/13/80 Site No. 4
Time Temperature °C
10:30 32
11:30 34
12:30 34
13:30 34
14:30 35
15:30 35
Time Temperature °C
10:00 27
11:00 27
12:00 27
13:00 28
14:00 27
15:00 26
Date: 8/04/80 Site No. 5
Time Temperature °C
20:00 23
22:30 20
Date: 8/07/80 Site No. 6
Time Temperature °C
19:30 28
22:30 27
-47-
-------
APPENDIX C
Calculation of Barrier Attenuation
The attenuation due to a rigid barrier was calculated by use of the
Moekawa barrier attenuation formula given by
A , ( 20 '<*10 (raifcVZTTjj +5 4SM, N > -0.2
b j 0, N K -0.2
Here N is the Fresel number which is a frequency and geometry dependent factor
defined by
/p)
N = j (A + B - d) where A is the wavelength of the sound, A is the distance
from the source to the top of the barrier, B is the distance from the top of
the barrier to the receiver and d is the direct line distance from source to
receiver. *
To obtain the attenuation of train noise by the retaining wall barrier to
be used in the depressed alternative, an octave-band analysis of a typical
train passby was conducted. The result of that analysis is shown in figure 7.
For each octave-band center frequency, an N was calculated and a barrier
attenuation calculated and then subtracted from the maximum level found by the
octave-band analysis. These adjusted maximums for each octave-band center
frequency where then combined by use of the formula
J Lmax }
(r i in I
L (total) = 10 logln (2 j 10 ) and this result was taken to be
(all bands J
the attenuated A-weighted Lmax-
For the barrier attenuation considered here, four separate cases were
calculated. The first two were the attenuation of the noise from the locomo-
tive at a distance of 4.3 m and 54.9 m from the barrier. The source of loco-
motive noise was assumed to be from the engine exhaust which is at the top of
the locomotive about 4.6 m from the level of the rails. The second two cases
were the attenuation of railcar noise. It was assumed that the major source
of railcar noise is the interaction between the rail and the car wheels.
Figure 8 gives a sectional view of the geometry considered in the calculation
of barrier attenuation.
*Reference
Beranek, Leo L., Noise and Vibration Control, McGraw-Hill Book Company,
New York, 1971. See section 7.6, "Attenuation by Barriers."
-48-
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OCTAVE PASS BANDS IN HERTZ
180
710
100
< 90
3.
80
70
v>
t/i
60
(/)
50
40
125
250
500
1000
2000
8000
30
10000
1000
100
FREQUENCY IN HERTZ
locomotives railcars
Tram No. 9, Site No. 4, 8/13/80
Figure 7. Octave-band analysis of typical train
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LD
y
£
m
v/
CN
CM
ro
Figure 8. Geometry of Barrier Attenuation
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