HomeMy WebLinkAbout3190; Rancho Santa Fe Road; Rancho Santa Fe Road Assessment District 86-5; 1986-07-01Ik-.
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ACOUSTICAL ANALYSIS STUDY
for
ASSESSMENT DISTRICT NO. 86-5
Report 86-006
prepared for:
City of Carlsbad
Office of the City Engineer
1200 Elm Avenue
Carlsbad, CA 92008-1989
prepared by:
Alexander Segal, Ph.D.
Consultant in Acoustics
5222 Trojan Ave. tt 316
San Diego, CA 92115
July 1986
Report 86-006
Assessment District No. 86-5
1. SUMMARY OF FINDINGS
Traffic on Rancho Santa Fe Road presently results in high levels
of noise affecting the existing residences located along the
road. Traffic noise impacts greatly depend on medium and heavy
truck traffic. Recently adopted Ordinance, v;hich bans trucks
weighting more than 7 tons from using the road, resulted in
traffic noise decrease in the area.
The field sound level measurements and the theoretical traffic
noise prediction calculations were performed in order to evaluate
traffic noise impacts on a number of the existing residences
located along Rancho Santa Fe Road between Olivenhain Road and
Melrose Avenue as illustrated on the topography cross-sections
provided by the City of Carlsbad Planning Department. Several
traffic flow alternatives were considered including the existing
traffic flow conditions (before and after the truck ban), and the
forecasted traffic flov/ conditions (v/ith and without the proposed
widening of Rancho Santa Fe Road). It was assumed that the
recently imposed truck ban would remain in the future.
The analysis revealed that traffic noise impacts on the majority
of the existing residences under investigation exceed the City of
Carlsbad General Plan exterior noise limit (Ldn=65 dB). After the
truck ban had been imposed, traffic noise decreased by at least 3
decibel. However, at some of the residences traffic noise still
exceeds Ldn=65 dB.
It is expected that in the future traffic flow and traffic noise
would increase. Since the road widening will result in the road
centeriine being located at larger distance from the existing
residences, traffic noise increase would be lower than that
anticipated from the forecasted traffic flow increase.
Analysis shows that the present (after the truck ban) and the
forecasted traffic noise impacts could be reduced to Ldn=65 dB by
3 to 7.5 ft high solid acoustical barriers placed betv/een the
residences under investigation and the road. In order to reduce
traffic noise impacts to Ldn=45 dB inside the residences, dual or
laminated windows might be needed. Some kind of mechanical
ventilation could also be required in order to provide a
habitable living environment inside the residences at the "closed
window" conditions.
Report 86-006
Assessment District No. 86-5
2. INTRODUCTION
This Acoustical Analysis is submitted in accord with the
agreement with the City of Carlsbad regarding the acoustical
evaluation of traffic noise impacts on the existing residences
located along Rancho Santa Fe Road between Olivenhain Road and
Melrose Avenue and shown on the topography cross-sections
provided by the City of Carlsbad Planning Department. Several
traffic flow alternatives, as specified by the City of Carisbad
Engineer, are considered.
The City of Carlsbad General Plan uses a Day-Night Average Sound
Level (Ldn) of 65 dB as a noise limit for the outside "noise
sensitive" residential areas (such as yards, patios, balconies,
etc.). The interior noise limit is Ldn=45 dB.
Since the existing and the forecasted traffic load on section of
Rancho Santa Fe Road under consideration is relatively high
(Average Daily Traffic CADT] in excess of 12,000 vehicles per
day), a potential exists that traffic noise impacts to the
residences aiong Rancho Santa Fe Road might exceed the City of
Carlsbad Noise Limits.
2. METHOD OF EXTERIOR NOISE EVALUATION
The acoustical conditions in the area under investigation were
evaluated using the direct sound level measurements and the
theoretical methods of traffic noise prediction.
The field noise measurements were made by a Metrosonics dB-306C
Metrologger Digital Sound Level Analyzer, which is a Type II
instrument in accord with the ANSI S 1.4-1971 requirements. The
Analyzer takes 4 samples of "A" Weighted sound levels per second
("Slow" time constant). Typically Metrosonics dB-306C was mounted
on a tripod four to five feet above the ground with a windscreen
fitted to the microphone. Before and after the noise level
measurements the meter was calibrated with a C-302 Acoustical
Calibrator.
Report 86-006
Assessment District No. 86-5
Traffic count v/as taken during the field sound level measurements
in order to aid in comparison analysis between the theoretical
and the field data.
The theoretical evaluation of traffic noise impacts v/as performed
on the IBM PC computer using a custom-made computer program. The
program is based on the Federal Highway Administration Traffic
Noise Prediction Model FHWA-RD-77-108 (1) modified for the
California conditions. The program uses the California Vehicle
Noise (Calveno) reference energy mean emission levels developed
by Caltrans in 1984 (2), and incorporates the new revised grade
corrections developed by Caltrans and presented at the January
1986 Transportation Research Board Annual Meeting (3).
Based either on the one-hour number of vehicles (HNV) or on the
average daily number of vehicles (ADT) information, traffic mix,
speed, and other traffic' flov/ and the project topography data,
the program estimates the one-hour equivalent sound level
CLeq(h)] and the Community Equivalent Noise Level (CNEL) at the
specified location. The program assumes that CNEL is 1.5 to 2 dB
higher than Leq(h). That is rather a conservative assumption for
typical residential roads since lower traffic volumes on weekends
and lower truck volumes on weekends and during the night hours
are ignored.
The program takes into account different sound propagation above
the ground conditions (drop-off rate). For acoustically hard
sites ("reflective" sites v/ith a site parameter ALPHA=0.0), the
calculations are performed using the propagation rate of 3 dB per
doubling of distance (3 dB/DD). For acoustically soft sites
("absorptive" sites with a site parameter ALPHA=0.5 and 4.5 dB/DD
propagation rate), the calculations are performed for both the
"soft" and the "hard" site conditions.
In order to describe potential noise impacts v/ithin the project,
the following community noise descriptors were used:
A-Weiqhted Sound Level (dB) - the sound level measured with the
utilization of the "A-weighting" frequency correction. This
correction weights the contribution of sounds of different
frequencies so that the response of the average human ear is
s imulated.
Equivalent Sound Level (LEQ or Leq) - the A-weighted level of a
continuous steady sound which contains the same total acoustical
energy over the averaging time period as the actual time varying
s ound.
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Report 86-006
Assessment District No. 86-5
Maximum sound level (Lmax) - the maximum sound level recorded
during the measurements.
One-Hour Equivalent Sound Level (Leq(h)) - the Leq over one hour
averaging period.
Community Noise Equivalent Level (CNEL) - a composite noise index
derived from the summation of hourly LEQ's over a 24-hour time
period with increasing weighting factors applied to the evening
(7:00 pm to 10:00 pm, + 5 dB) and the nighttime (10:00 pm to 7:00
am, + 10 dB) time periods.
Day-Night Average Sound Level (PNL or Ldn) - is identical to CNEL
except that no evening (7:00 pm to 10:00 pm) adjustment is used.
For most practical applications, CNEL and Ldn are considered to
be equal.
4. EXISTING NOISE ENVIRONMENT
In order to determine the existing traffic noise impacts along
the stretch of Rancho Santa Fe Road under investigation, the
field sound level measurements were made at several locations on
two Saturdays (April 12 and May 24, 1986) and on two Tuesdays
(April 29 and June 24, 1986). The noise readings were taken
during morning, mid-day and afternoon hours. The measurements
were performed before and after the new Ordinance v/hich bans
trucks weighting more than 7 tons from using the stretch of
Rancho Santa Fe Road between Olivenhain Road and Questhaven Road
v/as approved by the City of Carlsbad Council.
The first noise measurement location was along relatively level
part of Rancho Santa Fe Road north of Cadencia Road and about
several hundred feet south of the SDG&E easement. Surrounding
land is relatively level and vacant. Therefore, there was an
unobstructed viev/ to the road from the measurement location with
subtended angles within -80, +90 degrees. The noise readings were
taken at approximately 50 ft from the centeriine of Rancho Santa
Fe Road which at that location is a two lane road with posted
traffic speed of 45 mph.
The results of the sound level measurements at Location 1 with
the corresponding traffic flow data (number of automobiles,
medium and heavy trucks) recorded during each test are summarized
in Table 1.
Report 86-006
Assessment District No 86-5
Table 1
RESULTS OF THE FIELD SOUND LEVEL MEASUREMENTS AT LOCATION 1
Tes t
No .
Date Time Number
Auto
of
M.'
veh i c1e s
Tr. H.Tr.
Te s t
durat i on
min.sec
Leq Lma:
1 4-12 4-5p . m. 146 1 0 10 . 04 66 82
2 4-29 1-2p . m. 118 6 8 10 . 27 69 83
3 4-29 1-2p . m. 130 6 21 10 .33 73 86
4 4-29 1-2p . m. 127 8 19 10 . 35 71 85
5 6-24 6-9a . m. 180 4 1 10 . 58 68 84
6 6-24 8-9a . m 202 5 2 10 . 29 69 83
7 6-2 4 8-9a . m 153 5 1 10 . 34 68 81
8 6-24 8-9 a . m 154 4 0 11 . 11 67 81
9 6-24 9-10a .. m 153 5 3 11 . 17 68 82
10 6-24 9-10a . m 130 5 0 10 . 46 67 86
11 6-24 9-10a . m 179 6 3 11 . 45 69 87
The second noise measurement location was in front of the
existing residence at the south-west corner of Cadencia Street
and Rancho Santa Fe Road intersection. Rancho Santa Fe Road at
that location has 2 traffic lanes with the road grade ranging
from 2 to 6 percent. The noise readings were taken at roughly 30
ft from the road centeriine. There was an unobstructed view to
the road from the measurement -location with subtended angles of
about -90, +90 degrees. Posted traffic speed in the area is 45
mph.
The results of the sound level measurements at Location 2 with
the corresponding traffic flow data (number of automobiles,
medium and heavy trucks) recorded during each test are summarized
in Table 2.
Table 2
RESULTS OF THE FIELD SOUND LEVEL MEASUREMENTS AT LOCATION 2
Test Date Time Number of vehicles
No. Auto M.Tr. H.Tr.
Test
durat i on
min.sec
Leq Lmax
1 4-29 2-3p.m. 166 6 11
2 5-24 4-5p.m. 170 2 0
3 6-24 12-lp.m. 156 5 2
10 . 40
13.55
11.17
74
70
72
91
87
88
Report 86-006
Assessment District No. 86-5
The third noise measurement location was several hundred feet
south of intersection of Rancho Santa Fe Road v/ith Melrose
Avenue. Rancho Santa Fe Road at that location has 2 traffic lanes
and a left turn lane. Near the measurement location the road
grade was within 2 percent with significant grade increase
further to the north. Posted traffic speed is 45 mph. The noise
readings were taken at approximately 45 ft from the road
centeriine (Tests 1, 2, and 3), and at approximately 56 ft from
the road centeriine (Test 4). There was an unobstructed view to
the road from the measurement location v/ith subtended angles of
-90, +90 degrees.
The results of the sound level measurements at Location 3 with
the corresponding traffic flov/ data (number of automobiles,
medium and heavy trucks) recorded during each test are summarized
in Tab1e 3.
Table 3
RESULTS OF THE FIELD SOUND LEVEL MEASUREMENTS AT LOCATION 3
Test
No .
Date Time Number
Auto
of vehicles
M.Tr. H.Tr.
Test
durat ion
min.sec
Leq Lmax
1 4-12 3-4p.m. 148 4 0 10.02 68 81
2 4-12 4-5p.m. 153 1 0 10.10 68 80
3 4-29 2-3p.m. 83 9 14 4 . 38 75 89
4 4-29 2-3p.m. 152 7 20 10.25 71 86
In order to verify the validity of the theoretical traffic noise
prediction techniques planned to be used, traffic flow data
recorded during each test were transformed to the one-hour values
and based on these value the "calculated" Equivalent Sound Levels
CLeq(c)3 were estimated for all noise measurement locations.
Traffic speed of 45 mph was used in all calculations. The
calculated values (LeqCc3) were than compared with those obtained
during the field tests (LeqCm]). Since the results of the field
tests were recorded in decibels without the fractional portion
(integers), the results of .the acoustical calculations were also
converted to integers (by rounding the fractional portion) in
order to allow the comparison of identical variables. The
examples of the acoustical calculations are shown in Tables 1
through 10 in the Attachment.The final results are summarized in
Tables 4, 5, and 6.
Report 86-006
Assessment District No. 86-5
Table 4
THEORETICAL ANALYSIS OF THE FIELD RESULTS AT LOCATION 1
Test HNV % of Trucks Speed Leq C c ] Leq Cm] Leq C
No . M.Tr . H.Tr . mph (calc) (meas) Leq L
1 876 0 . 6 0 . 0 45 66 . 8 (67) 68 + 1
2 758 4.5 6 . 1 45 69.8 (70) 69 -1
3 893 3 . a 13.4 45 72 . 4 (72) 72 0
4 873 5 . 2 12 . 3 45 72 . 1 (72) 71 -1
5 1012 2 . 2 0 . 5 45 68 . 1 (68) 68 0
6 1197 2 . 4 1 . 0 45 69 . 2 (69) 69 0
7 903 3.1 0.6 45 67.9 (68) 68 0
8 848 2.5 0 . 0 45 67. 1 (67) 67 0
9 856 3 . 1 1 . 9 45 68 . 4 (68) 68 0
10 752 3.7 0 . 0 45 66 . 8 (67) 67 0
11 960 3 . 2 1 .6 45 68 . 7 (69) 69 0
Table 5
THEORETICAL ANALYSIS OF THE FIELD RESULTS AT LOCATION 2
Test HNV % of Trucks Speed Leq C c ] Leq Cm] Leq Cm]-
No . M.Tr . H.Tr . mph (calc) (meas) Leq C c]
1 1029 3 . 3 6.0 45 73.5 (74) 74 0
2 742 2.8 0 . 0 45 69.1 (69) 70 + 1
3 867 3 . 1 1 . 2 45 70.6 (71) 72 + 1
Report 86-006
Assessment District No. 86-5
Table 6
THEORETICAL ANALYSIS OF THE FIELD RESULTS AT LOCATION 3
Tes t HNV % of Trucks Speed Leq C c ] Leq Cm] Leq Cm]-
No . M.Tr . H.Tr . mph (calc) (meas) Leq C c ]
1 909 2.6 0 . 0 45 68.2 (68) 68 0
2 909 0.6 0 . 0 45 67.8 (68) 68 0
3 1374 8.5 13.2 45 75.3 (75) 75 0
4 1031 3.9 11.1 45 72.2 (72) 71 -1
As can be seen from Tables 4, 5, and
theoretical calculations are in a good
obtained during the field tests (some
explained by higher traffic speed during
presence of unusually loud vehicles in
reflections by the intervening topography,
theoretical noise prediction techniques
used to describe the existing and the
conditions in the area.
6, the results of the
agreement v/ith those
differences could be
the specific tests,
traffic flow, sound
etc.). Therefore, the
specified above can be
forecasted acoustical
The existing noise environment along the stretch of Rancho Santa
Fe Road under investigation was determined based on the traffic
flow information provided by the City of Carlsbad and the average
traffic mix and speed data obtained during the field tests.
According to the City of Carlsbad, the existing ADT on Rancho
Santa Fe Road between Olivenhain Road and La Costa Avenue is
within 12,700, and between La Costa Avenue and Melrose Avenue
traffic increases to ADT=14,400. The majority of the existing
residences along Rancho Santa Fe Road are located between La
Costa Avenue and Melrose Avenue where the traffic load is
greater.
For the purpose of the noise impact analysis, the City of
Carlsbad has selected 11 existing residences located along Rancho
Santa Fe Road between Olivenhain Road and Melrose Avenue. The
topography cross-sections of these residences, as specified by
the City of Carisbad, are presented on Fig. 1 through 6 in the
Attachment. The topography cross-sections represent the following
residential lots:
Report 86-006
Assessment District No. 86-5
North of La Costa Avenue
Secti on 1 -Lot 40 (At Cadencia Street, Revised C. T. 72-20)
Secti on 2 -Lot 48 (At Casca Way, Revised CT. 72-20) ;
Secti on 3 -Lot 49 (At Casca Way, Revised CT. 72-20 ) ;
Secti on 4 -Lot 54 (At Mus1o Lane, Revi sed C.T. 72 -20) ;
Secti on 5 -Lot 57 (At Mus1o Lane, Revised C.T. 72 -20) ;
Secti on 6 -Lot 92 (At Tr igo Lane, Revised C.T. 72 -20) ;
Sect ion 7 -Lot 93 (At Trigo Lane, Revised CT. 72 -20 ) ;
Secti on 8 -Lot 99 (At Piragua Street, Revised CT . 72-20);
Secti on 11 • - Lot at Agua Dulse (C. T. 72-20);
South of La Costa Avenue
Section 9 - Lot 126 (At Quebrada Circle, CT. 72-3);
Section 10 - Lot 129 (At Quebrada Court, CT. 72-3);
As has been specified above, the existing traffic load on Rancho
Santa Fe Road between Olivenhain Road and La Costa Avenue is
slightiy lower than that betv/een La Costa Avenue and Melrose
Avenue. In order to address "the worst case" conditions, the
calculations were performed assuming that the existing ADT is
14,400 aiong the entire stretch of Rancho Santa Fe Road under
investigation. Traffic speed of 45 mph was used in all
calculat ions.
Analysis of the weekday traffic count data revealed that during
the day-hours there v/as an average 4.2% medium and 9.4% heavy
trucks in the area before the truck ban, and that there v/as about
3% of medium and 1% of heavy trucks after the ban v/as imposed.
These data were further used in the theoretical noise prediction
analysis in order to address traffic noise impacts before and
after the truck ban.
According to the field observations, some of the existing
residences along Rancho Santa Fe Road are separated from the road
by fences and walls of different size and material. These walls
might provide some attenuation of traffic noise impacts. However,
since most of these walls are acoustically not "solid", their
sound attenuation effect was ignored during this analysis.
All calculations were performed for the "first floor" (5 ft above
the ground) observer position. The examples of the acoustical
calculations are presented in Tables 11 and 12 in the Attachment.
The final results of the acoustical calculations are summarized
in Table 7.
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Report 86-006
Assessment District No. 86-5
Table 7
TRAFFIC NOISE IMPACTS AT THE SELECTED CROSS-SECTIONS
(EXISTING CONDITIONS, NO BARRIERS)
Secti on Before the truck ban After the truck ban
No . Ldn Compiiance Ldn Comp1iance
in dB with Ldn=65 dB in dB • with Ldn=65 dB
1 74 + 9 71 + 6
2 74 + 9 71 + 6
3 73 + 8 70 + 5
4 73 + 8 70 + 5
5 74 + 9 71 + 6
6 74 + 9 71 + 6
7 75 + 10 71 + 6
8 74 + 9 71 + 6
9 66 + 1 61 -4
10 71 + 6 65 0
11 62 -3 56 -9
As can be seen, traffic noise impacts to most of the existing
residences under investigation significantiy exceed the Ldn=65 dB
limit established by the City of Car 1sbad. It also can be seen
that the noise impacts decreased by at least 3 dB after the truck
ban had been enforced.
The additional calculations were performed in order to determine
the existing traffic noise contour location. Since the existing
building structures provide different degree of shielding,
determination of the noise contour location within the already
developed areas is considered to' be not practical. Therefore, the
noise contour location on the undeveloped "level" iand was
addressed.
It was determined that before the truck ban the Ldn=65 dB traffic
noise contour was located somewhere at 200 to 220 ft from the
road centeriine. After the truck ban had been imposed, the Ldn of
65 dB noise contour is expected to be somewhere at 100 to 130 ft
from the road centeriine. For elevated or depressed (in relation
to the road elevation) areas distance to Ldn=65 dB noise contour
might be different.
11
Report 86-006
Assessment District No. 86-5
5. FUTURE NOISE ENVIRONMENT
Future developments in the area and anticipated improvements of
Rancho Santa Fe Road to the Prime Major Arterial standard v/ili
result in traffic noise impact increase. The City of Carlsbad
estimates that future traffic on Rancho Santa Fe Road v/ithout the
road widening (2 lane road) might increase to ADT of 20,000. With
the proposed road improvements to a 6 lane standard, the expected
ADT might reach 44,000.
The forecasted traffic fiow data were used in the theoretical
noise prediction analysis for determination of future acoustical
conditions in the area of interest. The results are summarized in
Table 8.
Table 8
TRAFFIC NOISE IMPACTS AT THE SELECTED CROSS-SECTIONS
(FUTURE CONDITIONS, NO BARRIERS)
Sect ion
No .
Without the wideninq With the wideninq Sect ion
No . Ldn
in dB
Compliance
with Ldn=65 dB
Ldn
in dB
Comp1iance
with Ldn=65 dB
1 72 + 7 73 + 8
2 72 + 7 74 + 9
3 71 + 6 73 + 8
4 71 + 6 73 + 8
5 72 + 7 74 + 9
6 72 + 7 74 + 9
7 73 + 8 74 + 9
8 72 + 7 74 + 9
9 62 -3 65 0
10 67 + 2 69 + 4
11 58 -7 59 -6
12
Report 86-006
Assessment District No. 86-5
The analysis shows that the forecasted traffic noise impacts on
the majority of the existing residences under investigation could
significantly exceed Ldn=65 dB outdoor noise limit established by
the City of Carisbad. The analysis also shows that after the road
widening, traffic noise impacts on the existing residences wouid
be by 1 to 2 dB higher than that v/ithout the widening. That sound
level increase is somewhat lower than could be anticipated from
the forecasted traffic flow increase by 220% after the road
widening (101og(44000/20000)=3.4 dB). The lower noise increase
can be explained by the fact that after the widening, the road
centeriine wouid be further from the existing residences than it
is now.
It was determined that without the road widening future Ldn=65 dB
traffic noise contour wouid be located somewhere at 120 to 150 ft
from the road centeriine ("level" topography). With the road
widening and the anticipated traffic increase, the Ldn=65 dB
noise contour wouid be located somewhere at 200 to 240 ft from
the road centeriine. As was mentioned above, for elevated or
depressed (in relation to the road elevation) areas distance to
the Ldn=65 dB noise contour could be different.
6. MITIGATION MEASURES
The analysis shows that the existing and the forecasted traffic
noise impacts on some of the existing residences along Rancho
Santa Fe Road might exceed the Ldn=65 dB noise level limit
established by the City Of Carlsbad. In order to reduce traffic
noise impacts to Ldn=65 dB of less, different noise mitigation
measures were considered. Since the acoustical barriers are the
most widely used measures for traffic noise mitigation,
appiication of the free standing solid acoustical barriers was
evaluated the first.
The City of Carlsbad typically considers 6 ft high soiid noise
attenuation walls as an acceptable noise mitigation alternative
(4). Therefore, the acoustical calculations were performed to
determine the noise attenuation effect of 6 ft high acoustical
barriers placed between the road and the existing residences
under the investigation. The calculations were performed for ail
4 traffic flow alternatives considered in this analysis. The
examples of the acoustical calculations are shown in Tables 13
and 14 in the Appendix. The final results are summarized in
Tables 9 and 10.
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Report 86-006
Assessment District No. 86-5
Table 9
TRAFFIC NOISE IMPACTS AT THE SELECTED CROSS-SECTIONS
(EXISTING CONDITIONS, 6 FT HIGH BARRIERS)
Sect ion
No .
Before the truck ban After the truck ban Sect ion
No . Ldn
in dB
Compliance
with Ldn=65 dB
Ldn
in dB
Comp1iance
with Ldn=65 dB
1 68 + 3 63 -2
2 68 + 3 63 -2
3 66 + 1 62 -3
4 66 + 1 61 -4
5 67 + 2 63 -2
6 68 + 3 63 -2
7 68 + 3 64 -1
8 68 + 3 64 -1
9 62 -3 Not requi red
10 66 + 1 Not requi red
11 Not requi red Not requi red
Table 10
TRAFFIC NOISE IMPACTS AT THE SELECTED CROSS-SECTIONS
(FUTURE CONDITIONS, 6 FT HIGH BARRIERS)
Section Without the wideninq With the widening
No. Ldn Compliance Ldn Compiiance
in dB with Ldn=65 dB in dB with Ldn=65 dB
1 64 -1 67 + 2
2 €5 0 67 + 2
3 63 -2 66 + 1
4 63 -2 65 0
5 64 -1 66 + 1
6 65 0 67 + 2
7 65 0 67 + 2
8 65 0 67 + 2
9 Not requi red Not requi red
10 62 -3 65 0
11 Not requi red Not requi red
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Report 86-006
Assessment District No. 86-5
As can be seen from Tables 9 and 10, at the "after
and "future without widening with the truck ban
alternatives, the 6 ft high soiid wails would
noise impacts on the "first floor" observers at
under investigation to Ldn=65 dB or less. However,
the truck ban" or "future with widening with
traffic flow conditions, traffic noise impacts
residences could still exceed Ldn = 65 dB even v/ith
acoustical barriers.
the truck ban"
traffic flow
reduce traffic
the residences
at the "before
the truck ban"
on some of the
the 6 ft high
The additional calculations v/ere performed to determine the
optimal acoustical barrier height needed for traffic noise
mitigation to Ldn=65 dB at ali cross-sections under the
consideration. The results of the calculations are summarized m
Tables 11 and 12.
Table 11
NOISE MITIGATION MEASURES FOR THE EXISTING CONDITIONS
(COMPLIANCE WITH Ldn=65 dB LIMIT)
Section Before the truck ban
No. traffic flow conditions
After the truck ban
traffic flow conditions
1 Wali (8 . 5 ' above pad) Wall (4.5' above pad)
2 • Wall (8 . 0 ' above pad) Wall (4.5' above pad)
3 Wall (6. 5' above pad) Wali (4.0' above pad)
4 Wail (6 . 5 ' above pad) Wail (4.0' above pad)
5 Wail (7. 0 ' above pad) Wall (5.0' above pad)
6 Wall ( 7 . 0 ' above pad) Wall (5.0' above pad)
7 Wall (7. 5 ' above pad) Wail (5.5' above pad)
8 Wall ( 8 . 0 ' above pad) Wall (5.0' above pad)
9 Wail ( 3 . 0 ' above road) Not requi red
10 Wai i (6. 5 ' above road ) Wall (3.0' above road)
11 Not requi red Not required
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Report 86-006
Assessment District No. 86-5
Table 12
NOISE MITIGATION MEASURES FOR THE FUTURE CONDITIONS
(COMPLIANCE WITH Ldn=65 dB LIMIT)
Section Without the road wideninq
No. (2 lane road)
With the road v/ideninq
(6 lane road)
1 Wail (5.5' above pad) Wail (7.0' above pad )
2 Wall (5.5' above pad) Wali (7.0' above pad )
3 Wai 1 (5.0' above pad) Wall (6.5' above pad)
4 Wall (5.0' above pad) Wall (6.0' above pad)
5 Wali (5.5' above pad) Wail (6.5' above pad)
6 Wali (6.0' above pad) Wail (6.5' above pad)
7 Wall (6.0' above pad) Wail (7.0' above pad)
8 Wal 1 (6.0' above pad) Wail (7.5' above pad )
9 Not requi red Not requi red
10 Wail (3.0' above road) Wali (5.0' above road)
11 Not requi red Not required
As follows from Tables 11 and 12, the present (after the truck
ban) and the forecasted traffic noise impacts could be reduced to
a Ldn=65 dB (for the "first floor" receptors) by placing of solid
acoustical barriers ranging in height from 3 to 7.5 ft between
the residences under investigation and the road. In order to
reduce traffic noise impacts existed before the truck ban, the
barriers with height of up to 8.5 ft wouid be required.
Since typical traffic noise mitigation barriers have little or no
sound attenuation effect for the upper floor rooms, it might be
expected that traffic noise impacts on the upper floor elevations
(if any) of residences located along Rancho Santa Fe Road might
exceed Ldn=65 dB limit even when noise barriers are installed. It
should be also mentioned that due to reflection of sound from the
building elements, in some cases noise impacts behind the noise
attenuation barriers could be slightly higher than that specified
above.
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Report 86-006
Assessment District No. 86-5
The noise attenuation barriers should be
(masonry, concrete, stucco on wood frame, 2
etc.) without any openings. A barrier that has
10% of its total area provides a maximum of
of solid design
inch thick wood,
openings totaling
4 dec ibei noi se
attenuation (5). Therefore, the intended openings in a barrier
(for drainage, etc.) should not exceed 1% of the total area, and
the construction specifications should require that all joints
are tightly sealed.
The barriers could contain the light transparent sections (1/8 to
1/4 inch safety glass, shatterproof plexiglass, etc.) and could
consist of the earth berms topped by the freestanding walls. For
depressed or elevated (in relation to the road grade) lots, the
barrier height might be lower than that for "level" lots.
The City of Carisbad uses Ldn=45 dB as the interior noise limit.
In order to reduce the exterior noise impacts specified above to
Ldn=45 dB, the buiiding envelope need to provide at least 20 to
30 decibel of noise reduction. Since sound attenuation of typical
building envelope at the "open v/indow" conditions is relatively
low ( somev/hat between 10 to 15 decibel depending on size of the
open area, room absorption, etc.), it can be expected that with
the windows open, the interior noise in the residences under
investigation might exceed 45 decibel.
In order to reduce the interior noise impact to Ldn = 45 dB, the
windows of the affected residences need to be closed and some
kind of mechanical ventilation need to be used to compensate for
the lost natural ventilation. Additionally, use of dual or
laminated glazing could be required in some windows, especially,
at the upper floor rooms.
Determination of more specific exterior and interior noise
mitigation measures shail be provided on the case by case basis.
It appears that the exterior and the interior noise analysis need
to be performed for ail future residences planned to be placed
within Rancho Santa Fe Road corridor. Traffic noise predictions
and the proposed noise mitigation measures contained in this
report are preliminary only and represent the best estimates
based on currentiy available information.
Alexander
Acous t ica.
fegai, Ph.D.
Eng ineer
17
Report 86-006
Assessment District No. 86-5
REt'liKENCES
1. Barry,T.M., and Reagan,J.A. (1978). "FHWA Highway Traffic
Noise Prediction Model," Report No. FHWA-RD-77-108 by the U.S.
Department of Transportation, Federal Highv/ay Administration.
2. Hendriks, R.W., (1984). "California Vehicle Noise Emission
Levels," Interim Report by Office of the Transportation
Laboratory, California Department of Transportation.
3. Hendriks, R.W., (1986). "Heavy Truck Noise Emission Levels on
Grades in California," Report by Office of the Transportation
Laboratory (Caltrans) to the Transportation Research Board Annual
Meet ing.
4. Letter from the City of Carlsbad Land Use Pianning Office
dated April 8, 1986.
5. The Noise Guidebook, A Reference Document for Implementing the
Department of Housing and Urban Development's Noise Policy,
(1985). U.S. Department of Housing and Urban Development, Office
of Community Pianning and Development.
18
0)
Figure 1. Cross-sections 1 and 2
^ •-^ --^^ •.SSSSSkk.v..^s,V|.'SS.k.k.^^-^C,..
I
1
Figure 2. Cross-sections 3 and 4
®
lk
Figure 3. Cross-sections 5 and 6
1
Figure 4, Cross-sections 7 and 6
V
Figure 5. Cross-sections 9 and 10
V
zz.y
1 /
/ /
Aie' /
30^
X
o
Figure 6. Cross-section 11
APPENDIX
REPORT 86-006
TABLE 1
TRAFFIC NOISE IMPACT CALCULATIONS
FHWA-RD-77-108 TRAFFIC NOISE PREDICTION MODEL
(MODIFIED FOR CALIFORNIA TRAFFIC CONDITIONS)
ROAD NAME - RANCHO SANTA FE ROAD
RECEPTOR LOCATION - LOCATION 1, TEST 1
TRAFFIC FLOW INFORMATION
HNV - 876.0
7. OF MEDIUM TRUCKS - 0.6
7. OF HEAVY TRUCKS - 0.0
SPEED IN MPH - 45.0
PROJECT GEOMETRY INFORMATION
SOURCE TO RECEIVER DISTAN CE 50. Q
SINGLE-LANE EQUIVALENT DISTANCE -49.6
BARRIER TO RECEIVER DISTANCE 0.0
ROAD ELEVATION -1.0
TOP OF BARRIER ELEVATION (WALL) -1.0
RECEIVER ELEVATION -=; n
ROAD GRADE (%) -1.0
LEFT ANGLE --80.0
RIGHT ANGLE -90.0
INTERMEDIATE RESULTS • OF CALCUL ATIONS CREFLEC TIVE^ SITE)
SOURCE Leq(h) FRESNEL SHIELDING Leq(h)
(NO BARRIER) NUMBER in dB iU ITH A BARRIER)
AUTOS 66.6 -3. 76 0.0 66.6
M.TRUCKS 52.7 -3.94 Q.O =;•- T
H.TRUCKS 39.5 -4.38 0.0 -IQ c;
FINAL RESULTS OF CALCULATIONS (WITH SHIELDING)
TOTAL Led(h)- - 'REFLECTIVE' SITE (ALPHA=0.0) - 66.3 dl
EXPECTED CNEL - 'REFLECTIVE' SITE - 68 to 69 dB
APPENDIX
REPORT 86-0 06
TABLE 2
TRAFFIC NOISE IMPACT CALCULATIONS
FHWA-RD-77-108 TRAFFIC NOISE PREDICTION MODEL
(MODIFIED FOR CALIFORNIA TRAFFIC CONDITIONS)
ROAD NAME - RANCHO SANTA FE ROAD
RECEPTOR LOCATION - LOCATION 1, TEST 3
TRAFFIC FLOW INFORMATION
.HNV - 893,0
Z OF MEDIUM TRUCKS - 3.8-
>: OF HEAVY TRUCKS - 13.4
SPEED IN MPH - 45.0
PROJECT GEOMETRY INFORMATION
SOURCE TO RECEIVER DISTANCE 50.0
SINGLE-LANE EQUIVALENT DISTANCE -49. 6
BARRIER TO RECEIVER DISTANCE O.C
ROAD ELEVATION -1.0
TOP OF BARRIER ELEVATION (WALL) -1.0
RECEIVER ELEVATION -5.0
ROAD GRADE (X) -i .0
LEFT ANGLE --80.0
RIGHT ANGLE -90.0
INTERMEDIATE RESULTS OF CALCULATIONS ('REFLECTIVE' SITE)
SOURCE Leq\h) FRESNEL SHIELDING Leq (h)
(NO BARRIER) NUMBER in .dB (WITH A BARRIER)
AUTOS 65.9 -3.76 0.0 65. C
/ M.TRUCKS 60.8 -3.94 •.0 60. o
H.TRUCKS 70.8 -4,38 0.0 70. a
FINAL RESULTS OF CALCULATION S (WITH SHIELDING)
TOTAL Led(h) - 'REFLECTIVE' SITE (ALPHA=C.O) - 72.4 dB
EXPECTED CNEL - 'REFLECTIVE' SITE - 73 to 74 dB
APPENDIX
REPORT 86-006
TABLE 3
TRAFFIC NOISE IMPACT CALCULATIONS
FHWA-RD-77-108 TRAFFIC NOISE PREDICTION MODEL
(MODIFIED FOR CALIFORNIA TRAFFIC CONDITIONS)
ROAD NAME - RANCHO SANTA FE ROAD
RECEPTOR LOCATION - LOCATION 1, TEST 7
TRAFFIC FLOW INFORMATION
HNV - 903.0
'I. OF MEDIUM TRUCKS - 3.1
% OF HEAVY TRUCKS - 0.6
SPEED IN MPH - 45.0
PROJECT GEOMETRY INFORMATI? JN
SOURCE TO RECEIVER DISTANCE
3I.NGLE-LANE EQUIVALENT DISTANCE -
BARRIER TO RECEIVER DISTANCE
ROAD ELEVATION
TOP OF BARRIER ELEVATION (WALL) -
RECEIVER ELEVATION
ROAD GRADE (7.)
LEFT ANGLE
RIGHT ANGLE
50.0
49.6
0.0
1.0
1.0
5.0
1.0
-SO.O
90. D
INTERMEDIATE RESULTS OF CALCULATIONS ('REFLECTIVE' SITE)
SOURCE Leq(h) FRESNEL
(NO BARRIER) NUMBER
SHIELDING
in dB
Leq(h)
(WITH A BARRIER)
AUTOS 66,6 -3.76 Q.O
M.TRUCKS 60.0 -3.94 O.Q 60.0
H.TRUCKS 57.4 -4,38 0,0 57.4
FINAL RESULTS OF CALCULATIONS (WITH SHIELDING)
TOTAL Led(h) - 'REFLECTIVE' SITE (.ALPHA=0.0) - 67.9 dB
EXPECTED CNEL - 'REFLECTIVE' SITE - 69" to 70 dB
APPENDIX
REPORT 86-0 06
TABLE 4
TRAFFIC NOISE IMPACT CALCULATIONS
FHWA-RD-77-108 TRAFFIC NOISE PREDICTION MODEL
(MODIFIED FOR CALIFORNIA TRAFFIC CONDITIONS)
ROAD NAME - RANCHO SANTA FE ROAD
RECEPTOR LOCATION - LOCATION 1, TEST 9
TRAFFIC FLOW I MFORMATION
HNV - S56.0
% OF MEDIUM TRUCKS - 3.1
% OF HEAVY TRUCKS - 1.9
SPEED IN MPH - 45.0
PROJECT GEOMETRY INFORMATION
SOURCE TO RECEIVER DISTANCE
SINGLE-LANE EQUIVALENT DISTANCE -
BARRIER TO RECEIVER DISTANCE 0,0
ROAD ELEVATION 1.0
TOP OF BARRIER ELEVATION (WALL) -1.0
RECEIVER ELEVATION 5,0
ROAD GRADE (%> 1.0
LEFT ANGLE -80.0
RIGHT ANGLE 90.0
[NTERMEDIATE RESULTS OF CALCULATIONS ('REFLECTIVE' SITE)
SOURCE Leq(h) FRESNEL SHIELDING Leq ( h )
(NO BARRIER) NUMBER in dB (WI TH A ' BARRIE li j
AUTOS 66. 3 -3.76 0.0 66.
M.TRUCKS 59.8 -3,94 0,0 59. O
H.TRUCKS 62. 2 -4,38 0,0 62.
INAL RESULTS « OF CALCULATIONS (WITH SHIEL •DING)
TOTAL Led (h) 'REFLECTIVE' SITE (ALPHA=n.O) -68. 4 dB
•*•*•*•*•*•*•***•***#******•*#•* •***.Ji-*.)(.***-S.*
EXPECTED CNEL - 'REFLECTIVE' SITE - 69 to 70 dB
**#*•*-tf •*•»*•*•*•***•#*-*•* •^•S-»-*-M--i?-*-S-#-fS--****
APPENDIX
REPORT 86-006
TABLE 5
TRAFFIC NOISE IMPACT CALCULATIONS
FHWA-RD-77-108 TRAFFIC NOISE PREDICTION MODEL
(MODIFIED FOR CALIFORNIA TRAFFIC CONDITIONS)
ROAD NAME - RANCHO SANTA FE ROAD
RECEPTOR LOCATION - LOCATION 1, TEST li
TRAFFIC FLOW INFORMATIOf
HNV - 960.0
'/. OF MEDIUM TRUCKS - 3.2
"/. OF HEAVY TRUCKS - 1.6
SPEED IN MPH - 45.0
PROJECT GEOMETRY INFORMATION
SOURCE TO RECEIVER DISTAN CE 50.0
SINGLE-LANE EQUIVALENT DISTANCE -49.6
BARRIER TO RECEIVER DISTANCE 0,0
ROAD ELEVATION -1.0
TOP OF BARRIER ELEVATION (WALL) -1.0
RECEIVER ELEVATION -5.0
ROAD GRADE (7.) -1,0
LEFT ANGLE --80.0
RIGHT ANGLE -90.0
INTERMEDIATE RESULTS OF CALCULATIONS ('RE ELECTIVE' SITE)
SOURCE Leq(h) FRESNEL SHIELDING Lsq(h)
(NO BARRIER) NUMBER in dB (WITH A BARRIER)
AUTOS 66.9 -3.76 0.0 66,9
M.TRUCKS 60.4 -3.94 Q.O 60.4
H.TRUCKS 61.9 -4.38 O.Q 61.9
FINAL RESULTS OF CALCULATIONS (WITH SHIELDING)
TOTAL Led(h) - 'REFLECTIVE' SITE (ALPHA=0.0) - 68.7 dB
EXPECTED CNEL - 'REFLECTIVE' SITE - 70 to 71 dB
APPENDIX
REPORT 86-006
TABLE 6
TRAFFIC NOISE IMPACT CALCULATIONS
FHWA-RD-77-108 TRAFFIC NOISE PREDICTION MODEL
(MODIFIED FOR CALIFORNIA TRAFFIC CONDITIONS)
ROAD NAME - RANCHO SANTA FE ROAD
RECEPTOR LOCATION - LOCATION 2, TEST 1
TRAFFIC FLOW INFORMATION
HNV - 1029.0
7. OF MEDIUM TRUCKS
% OF HEAVY TRUCKS - 6.0
SPEED IN MPH - 45.0
PROJECT GEOMETRY INFORMATION
SOURCE TO RECEIVER DISTANCE - 30,0
SINGLE-LANE EQUIVALENT DISTANCE - 29.4
BARRIER TO RECEIVER DISTANCE - 0,0
ROAD ELEVATION - 1,0
TOP OF BARRIER ELEVATION (WALL) - 1.0
RECEIVER ELEVATION - 5.0
ROAD GRADE (7,) - 4,0
LEFT ANGLE - -90,0
RIGHT ANGLE - 90.0
INTERMEDIATE RESULTS OF CALCULATIONS ('REFLECTIVE' Slit)
SOURCE
(NO
Leq(h)
BARRIER)
FRESNEL SHIELDING Leg
NUMBER in dB (WITH A
(h)
BARRIER)
AUTOS
M.TRUCKS
H.TRUCKS
69.5
63.4
70.6
-3.65 0.0 69.
-3.95 0.0 63.
-4,70 0.0 70,
1=1
4
i.
FINAL RESULTS OF CALCULATIONS (WITH SHIELDING)
TOTAL Lsd(h) 'REFLE CTIVE' SITE (ALPHA=0.0) 73.5 dB
EXPECTED CNEL - 'REFLECTIVE' SITE - 74 to 75 dB
•***•)(••!<••);••*•***•*•?(•#*•«•**•* •it
APPENDIX
REPORT 86-006
TABLE 7
TRAFFIC NOISE IMPACT CALCULATIONS
FHWA-RD-77-108 TRAFFIC NOISE PREDICTION MODEL
(MODIFIED FOR CALIFORNIA TRAFFIC CONDITIONS)
ROAD NAME - RANCHO SANTA FE ROAD
RECEPTOR LOCATION - LOCATION 2, TEST 3
TRAFFIC FLOW INFORMATION
HNV - 867.0
% OF MEDIUM TRUCKS - 3.l'
y. OF HEAVY TRUCKS - 1.2
SPEED IN MPH - 45.0
PROJECT GEOMETRY INFORMATION
SOURCE TO RECEIVER DISTANCE - 30.0
SINGLE-LANE EQUIVALENT DISTANCE - 29.4
BARRIER TO RECEIVER DISTANCE - 0.0
ROAD ELEVATION -1,0
TOP OF BARRIER ELEVATION (WALL) -1.0
RECEIVER ELEVATION -5.0
ROAD GRADE (X) -4.0
LEFT ANGLE --90.0
RIGHT ANGLE -90.0
INTERMEDIATE RESULTS OF CALCULA TIONS ('REFLECT IVE' SITE)
SOURCE Leq(h) FRESNEL SHIELDING Leq(h)
(NO BARRIER) NUMBER in dB (WI TH A BARRIER)
AUTOS 69.0 -3. 65 Q.O 69.0
M.TRUCKS 62.3 -3.95 0.0 62.3
H.TRUCKS 62.9 -4.70 0.0 62.9
FINAL RESULTS OF CALCULATIONS (WITH SHIELDING)
TOTAL Led(h) - 'REFLECTIVE' SITE (ALPHA=0.0) - 70.6 dB
* it -if ***•**•** •it -it *-it-it-it-i^
EXPECTED CNEL - 'REFLECTIVE' SITE - 71 tc 72 dB
*-it * •it-it *-it-it-it * •* -it-it-it-it-it-it-it *
APPENDIX
REPORT 86-006
TABLE 8
TRAFFIC NOISE IMPACT CALCULATIONS
FHWA-RD-77-108 TRAFFIC NOISE PRED,ICTION MODEL
(MODIFIED FOR CALIFORNIA TRAFFIC' CONDITIONS)
ROAD NAME - RANCHO SANTA FE ROAD
RECEPTOR LOCATION - LOCATION 3, TEST 1
TRAFFIC FLOW INFORMATION
HNV - 909.0
X OF MEDIUM TRUCKS - 2.6
X OF HEAVY TRUCKS - 0.0
SPEED IN MPH - 45.0
PROJECT GEOMETRY INFORMATION
SOURCE TO RECEIVER DISTANCE - 45.0
SINGLE-LANE EQUIVALENT DISTANCE - 44.6
BARRIER TO RECEIVER DISTANCE - 0.0
ROAD ELEVATION - 1.0
TOP OF BARRIER ELEVATION (WALL) - 1,0
RECEIVER ELEVATION - 5.0
ROAD GRADE (7.) - 2.0
LEFT ANGLE - -90.0
RIGHT ANGLE - 90.0
INTERMEDIATE RESULTS OF CALCULATIONS ('REFLECTIVE' SITE)
SOURCE Leq(h) FRESNEL SHIELDIiNG Leq(h)
(NO BARRIER) NUMBER in dB (WITH A BARRIER)
n AUTOS 67.4 -3.74 O.C
M.TRUCKS 60.0 -3.94 0.0 60.0
H.TRUCKS 40.3 -4.44 0.0 40.3
FINAL RESULTS OF CALCULATIONS (WITH SHIELDING)
TOTAL Led(h) - 'REFLECTIVE' SITE (ALPHA=0.0) - 68.2 dB
* •it ***-it •it-it-it-it-it-it-it-it-it #-it-it-it-it •it *-it •*
EXPECTED CNEL - 'REFLECTIVE' SITE - 69 to 70 dB
•it*-it*-it****-)t-it*-it-it*****-it********.it-it***-it**
APPENDIX
REPORT 86-006
TABLE 9
TRAFFIC NOISE IMPACT CALCULATIONS
FHWA-RD-77-108 TRAFFIC NOISE PREDICTION MODEL
(MODIFIED FOR CALIFORNIA TRAFFIC CONDITIONS)
ROAD NAME - RANCHO SANTA FE ROAD
RECEPTOR LOCATION - LOCATION 3, TEST 3
•RAFFIC FLOW INFORMATION
HNV . - 1374.0
X OF MEDIUM TRUCKS - 8,5
X OF HEAVY TRUCKS - 13.2
SPEED IN MPH - 45.0
PROJECT GEOMETRY INFORMATION
SOURCE TO RECEIVER DISTANCE 45, 0
SINGLE-LANE EQUIVALENT DISTANCE -44. 6
BARRIER TO RECEIVER DISTANCE 0, 0
ROAD ELEVATION 1. n
TOP OF BARRIER ELEVATION (WALL) -1. 0
RECEIVER ELEVATION 5. 0
ROAD GRADE (X) 0
LEFT ANGLE -90. 0
RIGHT ANGLE 90. 0
INTERMEDIATE RESULTS OF CALCULATIONS ('REFLECTIVE' SITE)
SOURCE Leq(h) FRESNEL SHIELDING Leq(h)
(NO BARRIER) NUMBER in dB (WITH A BARRIER)
AUTOS 63.3 -3.74 0.0 68.3
M.TRUCKS 66.9 -3.94 0.0 66.9
H.TRUCKS 73.3 -4.44 0.0 73.3
FINAL RESULTS OF CALCULATIONS (WITH SHIELDING)
TOTAL Led(h) - 'REFLECTIVE'. SITE (ALPHA=0.0) - 75.2 dB
******-it**-it-it***-it#*-)t*-it#****it-it-it****#***-it-it-it*
EXPECTED CNEL - 'REFLECTIVE' SITE - 76 to 77 dB
**###***^it*-***^it-)t-it**-it*-it**-it*-it**^)t-it**-it
APPENDIX
REPORT 86-0 06
TABLE 10
TRAFFIC NOISE IMPACT CALCULATIONS
FHWA-RD-77-108 TRAFFIC NOISE PREDICTION MODEL
(MODIFIED FOR CALIFORNIA TRAFFIC CONDITIONS)
ROAD NAME - RANCHO SANTA FE ROAD
RECEPTOR LOCATION - LOCATION 3, TEST 4
TRAFFIC FLOW INFORMATION
HNV - 1031.Q
X OF MEDIUM TRUCKS - 3.9
X OF HEAVY TRUCKS - 11.1
SPEED IN MPH - 45.0
PROJECT GEOMETRY INFORMATION
SOURCE TO RECEIVER DISTAN CE 56.0
SINGLE-LANE EQUIVALENT DI STANCE -55.7
BARRIER TO RECEIVER DISTANCE 0.0
ROAD ELEVATION -1.0
TOP OF BARRIER ELEVATION (WALL) -1.0
RECEIVER ELEVATION -=; n
_J 3 Ul
ROAD GRADE (X) -.ii o U
LEFT ANGLE --90.0
RIGHT ANGLE -90.0
INTERMEDIATE RESULTS OF CALCUL ATIONS CREFL .ECTIVE' SI i E)
SOURCE Leq(h) FRESNEL SHIELDING Leq (h)
(NO BARRIER) NUMBER m dB (WITH A BARRIER)
AUTOS 66.4 -3.77 0.0 66. 4
M.TRUCKS 61.3 -3, 93 Q.O L 1
Win
H.TRUCKS 70.4 -4, 33 0.0 70. 4
FINAL RESULTS OF CALCULATIONS (WITH SHIELDING)
TOTAL Led(h) - 'REFLECTIVE' SITE (ALPHA=O.Q) - 72.2 dB
TOTAL Leq(h) - 'SOFT' SITE (ALPHA=0.5) - 70.8 dB
*-it-it •it-it-it * * * * * •it-it-it * * * *-it-it-it-it-it *-it * * it *
EXPECTED CNEL - 'REFLECTIVE' SITE - 73 to 74 dB
EXPECTED CNEL - 'SOFT' SITE - 72 to 73 dB
•it •it * * * *-it * * *-it *-it-it-it-it •* * * *-it * •it *-it-it it * * *
APPENDIX
REPORT 86-0 06
TABLE 11
TRAFFIC NOISE IMPACT CALCULATIONS
FHWA-RD-77-108 TRAFFIC NOISE PREDICTION MODEL
(MODIFIED FOR CALIFORNIA TRAFFIC CONDITIONS)
ROAD NAME - RANCHO SANTA FE ROAD
RECEPTOR LOCATION - SECTION 1, NO BARRIER, BEFORE THE TRUCK BAN
TRAFFIC FLOW INFORMATION
ADT - 14400.0
X OF MEDIUM TRUCKS - 4,2
X OF HEAVY TRUCKS - 9.4
SPEED IN MPH - 45.0
PROJECT GEOMETRY INFORMATION
SOURCE TO RECEIVER DISTANCE - 43.0
SINGLE-LANE EQUIVALENT DISTANCE - 42.3
BARRIER TO RECEIVER DISTANCE - 15.0
ROAD ELEVATION . - 506.3
TOP OF BARRIER ELEVATION (WALL) - 507,2
RECEIVER ELEVATION - 512.2
ROAD GRADE (X) - 2.0
LEFT ANGLE - -90.0
RIGHT ANGLE - 90.0
INTERMEDIATE RESULTS OF CALCULAT IONS CREF! .ECTIVE' SITE)
SOURCE Leq(h) FRESNEL SHIELDING Leq(h)
(NO BARRIER) NUMBER X I 1 UJ-< (WITH A BARRIER)
AUTOS 66.8 -0.41 0,0 L L O
'—•Ul n U
M.TRUCKS 61.9 -0.68 0,0 61.9
H.TRUCKS 69.9 -1.63 0,0 69. 9
FINAL RESULTS OF CALCULATIONS (WITH SHIELDING)
TOTAL Led(h) - 'REFLECTIVE' SITE (ALPHA=0.0)
•it**it****it-it****-it^it*-it*-it****-it-it****-)t-it^
EXPECTED CNEL - 'REFLECTIVE' SITE - 73 to 74 dB
•it * * *-it-it #-it •it •it * *-it •it * * * it-it * •it •* •it-it-it *-it •* * * *
APPENDIX
REPORT 86-0 06
TABLE 12
TRAFFIC NOISE IMPACT CALCULATIONS
FHWA-RD-77-108 TRAFFIC NOISE PREDICTION MODEL
(MODIFIED FOR CALIFORNIA TRAFFIC CONDITIONS)
ROAD NAME - RANCHO SANTA FE ROAD
RECEPTOR LOCATION - SECTION 1, NO BARRIER, AFTER THE TRUCK 3A^
TRAFFIC FLOW INFORMATION
ADT - 14400.0
X OF MEDIUM TRUCKS - 3.0
X OF HEAVY TRUCKS - 1.0
SPEED IN MPH - 45.0
PROJECT GEOMETRY INFORMATION
SOURCE TO RECEIVER DISTANCE 43. 0
SI.NGLE-LANE EQUIVALENT DISTANCE -42. •.J
BARRIER TO RECEIVER DISTANCE H 1= •i -1 . 0
ROAD ELEVATION 506.
TOP OF BARRIER ELEVATION (WALL) -507.
RECEIVER ELEVATION 512.
ROAD GRADE (X) Zi. 3 0
LEFT ANGLE -90. i"
RIGHT ANGLE 90, Q
INTERMEDIATE RESULTS OF CALCULATIONS ('REFLECT IVE' SITE)
SOURCE
(NO
Leq(h)
BARRIER)
FRESNEL SHIELDING
NUMBER in dB (WI
Leq
TH A
(ff)
BARRIER)
AUTOS
M,TRUCKS
H,TRUCKS
67,2
60.5
60.2
-0.41 O.Q
-0.68 O.Q
-1.63 0.0
i."7
LJ / •
60.
LJO B
5
FINAL RESULTS OF CALCULATIONS (WITH SHIEL DING)
TOTAL Lsd(h) ' REEL ECTIVE' SITE (ALPHA=0.0) -
•it-it * it-it it it-it it * * *-it-it * * -it *-it-it *-it-it ^
EXPECTED CNEL - 'REFLECTIVE' SITE - 70 to 71 dB
itit-Sit*it*it-Sitit*it*it*ititititititititititit-itit-!t-*itit-jt
APPENDIX
REPORT 86-0 06
TABLE 13
TRAFFIC NOISE IMPACT CALCULATIONS
FHWA-RD-77-108 TRAFFIC NOISE PREDICTION MODEL
(MODIFIED FOR CALIFORNIA TRAFFIC CONDITIONS)
ROAD NAME - RANCHO SANTA FE ROAD
RECEPTOR LOCATION - SECTION 1, 6' BARRIER, BEFORE THE TRUCK BAN
TRAFFI C FLOW INFORMATION
ADT
X OF MEDIUM TRUCKS
X OF HEAVY TRUCKS
SPEED IN MPH
14400.0
4. 2
9. 4
45.0
PROJECT GEOMETRY INFORMATION
SOURCE TO RECEIVER DISTANCE
SINGLE-LANE EQUIVALENT DISTANCE -
BARRIER TO RECEIVER DISTANCE
ROAD ELEVATION
TOP OF BARRIER ELEVATION (WALL) -
RECEIVER ELEVATION
ROAD GRADE (X)
LEFT ANGLE
RIGHT ANGLE
43.0
42. 3
15.0
506.3
513.2
512.2
2.0
-90.0
90.0
INTERMEDIATE RESULTS OF CALCULATIONS ('REFLECTIVE' SITE)
SOURCE Leq(h)
(NO BARRIER)
FRESNEL
NUMBER
SHIELDING Leq(h)
in dB (WITH A BARRIER)
AUTOS 66.8
M,TRUCKS 61.9
H.TRUCKS 69.9
0.47
0.26
0.00
-8.4 53.4
-7.2 54.7
-5.0 64.9
FINAL RESULTS OF CALCULATIONS (WITH SHIELDING)
TOTAL L8d(h) - 'REFLECTIVE' SITS (ALPHA=0.0)
it it-it-it it it*it it it-it it it it it-it it*it it it it it it it it it it it it it i^
EXPECTED CNEL - 'REFLECTIVE' SITE - 67 to 63 dB
it it it * ii-it * it it it it it it •* it it-it it it it it it it it it it it *-it it it it * i^
APPENDIX
REPORT 86-0 06
TABLE 14
TRAFFIC NOISE IMPACT CALCULATIONS
FHWA-RD-77-108 TRAFFIC NOISE PREDICTION MODEL
(MODIFIED FOR CALIFORNIA TRAFFIC CONDITIONS)
ROAD NAME - RANCHO SANTA FE ROAD
RECEPTOR LOCATION - SECTION 1, 6' BARRIER, AFTER THE TRUCK BAN
TRAFFIC FLOW INFORMATION
ADT - 14400.0
X OF MEDIUM TRUCKS - 3,0
X OF HEAVY TRUCKS - 1.0
SPEED IN MPH - 45.0
SOURCE TO RECEIVER DISTANCE - 43=0
SINGLE-LANE EQUIVALENT DISTANCE - 42.3
BARRIER TO RECEIVER DISTANCE - 15.0
ROAD ELEVATION - 506,3
TOP OF BARRIER ELEVATION (WALL) - 513.2
RECEIVER ELEVATION - 512.2
ROAD GRADE (X) - 2.0
LEFT ANGLE - -90.0
RIGHT ANGLE - 90.0
INTERMEDIATE RESULTS OF CALCULATIONS ('REFLECTIVE' SITE)
SOURCE Leq(h) FRESNEL SHIELDING Leq(h)
(NO BARRIER) NUMBER in dB (WITH A BARRIER)
AUTOS 67.2 0.47 -8.4 58.8
M.TRUCKS 60.5 0,26 -7,2 53.2
H.TRUCKS 60,2 0.00 -5,0 55.2
FINAL RESULTS OF CALCULATIONS (WITH SHIELDING)
TOTAL Led(h) - 'REFLECTIVE' SITE (ALPHA=Q.Q) - 61.2 dB
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EXPECTED CNEL - 'REFLECTIVE' SITE - 62 to 63 dB
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