1、 Standard Method of Test for Determining the Influence of Road Surfaces on Vehicle Noise Using the Statistical Isolated Pass-By (SIP) Method AASHTO Designation: TP 98-13 (2015)1American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C
2、. 20001 TS-5a TP 98-1 AASHTO Standard Method of Test for Determining the Influence of Road Surfaces on Vehicle Noise Using the Statistical Isolated Pass-By (SIP) Method AASHTO Designation: TP 98-13 (2015)11. SCOPE 1.1. This test method describes a procedure for measuring the influence of road surfac
3、es on highway traffic noise. The Statistical Isolated Pass-By (SIP) Method provides a quantitative measure of the sound pressure level at locations adjacent to a roadway. The SIP method allows for the comparison of vehicle noise on roadways of varying surfaces and across studies by comparing measure
4、d sound levels to a reference noise curve. 1.2. Measurements capture the sound pressure level from isolated vehicles in existing traffic. The SIP method is to be applied on roadways where measuring sound levels from single-vehicle pass-by events is possible without contamination from sound from othe
5、r vehicles. 1.3. This standard is intended for use by acoustic professionals. Competency with acoustical measurement and analysis techniques is assumed. 1.4. This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns
6、 associated with its use. It is the responsibility of the user of this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: TP 76, Measurement of Tire/Pavement
7、Noise Using the On-Board Sound Intensity (OBSI) Method TP 99, Determining the Influence of Road Surfaces on Traffic Noise Using the Continuous-Flow Traffic Time-Integrated Method (CTIM) 2.2. ASTM Standard: F2493, Standard Specification for P225/60R16 97S Radial Standard Reference Test Tire 2.3. FHWA
8、 Reports: FHWA-PD-96-008, Development of National Reference Energy Mean Emission Levels for the FHWA Traffic Noise Model (FHWA TNM), Version 1.0 FHWA-PD-96-009, FHWA Traffic Noise Model (FHWA TNM): Users Guide, TNM Version 2.5 Addendum, April 2004 FHWA-PD-96-010, FHWA Traffic Noise Model (FHWA TNM),
9、 Version 1.0: Technical Manual, 2004, update sheets available from FHWA 2016 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-5a TP 98-2 AASHTO FHWA-PD-96-046, Measurement of Highway-Related Noise, Section
10、 4: Existing-Noise Measurements in the Vicinity of Highways 2.4. IEC Standards: IEC 60942: 2003, ElectroacousticsSound Calibrators IEC 61260: 1995, ElectroacousticsOctave-Band and Fractional-Octave-Band Filters IEC 61672-1: 2002, ElectroacousticsSound Level MetersPart 1: Specifications 2.5. ANSI Sta
11、ndard: S1.42: 2001 (R2006), American National Standard Design Response of Weighting Networks for Acoustical Measurements 3. TERMINOLOGY 3.1. Definitions: 3.1.1. Continuous-Flow Traffic Time-Integrated Method (CTIM)a test method for measuring the influence of road surfaces on highway traffic noise. T
12、he CTIM method captures the sound from existing traffic for all vehicles on all roadway lanes and includes propagation effects over the roadway pavement and adjacent terrain to the nearby measurement location. 3.1.2. data setthe data collected to determine the reported Statistical Isolated Pass-By i
13、ndex (SIPI). 3.1.3. designated speedthe average of all pass-by vehicle speeds for a single vehicle category. 3.1.4. maximum sound levelthe highest sound pressure level recorded by the measuring instrument during a vehicle pass-by, using the A-weighted frequency network and a fast sound level meter r
14、esponse time (0.125-s exponential average). 3.1.5. measured vehicle sound level, Lvehthe sound level determined at the designated speed from a regression line of the maximum A-weighted sound pressure level versus the logarithm of vehicle speed, calculated for each vehicle category for the measured d
15、ata for a single microphone position either 25 ft or 50 ft (7.6 m or 15.2 m) from the center of the travel lane for a single pavement type. 3.1.6. measurement perioda period of time over which measurements are made during one site visit. A data set may combine one or more consecutive measurement per
16、iods to capture enough data to properly represent the site. 3.1.7. intensity (OBSI) methoda measurement procedure to evaluate the tire/pavement noise component resulting from the interaction of an ASTM F2493, Standard Reference Test Tire (SRTT) on a pavement surface. Sound intensity measurements are
17、 taken at defined locations near the tire/pavement interface. 3.1.8. powertrain noisethe noise generated from the powertrain, including the vehicle engine, exhaust system, air intake, fans, transmission, differential, and axles. 3.1.9. reference noise curvethe reference noise curve is extracted from
18、 the portion of the Reference Energy Mean Emission Level (REMEL) curve that is primarily attributed to tire/pavement noise (FHWA-PD-96-008). The reference noise curve is defined as A log10 (speed in mph) + B. The coefficients for each vehicle category are shown in Table 1 for the 50-ft (15.2-m) posi
19、tion (extracted from FHWA-PD-96-008, Section 7.4) and in Table 2 for the 25-ft (7.6-m) position calculated by shifting the 50-ft (15.2-m) curve up by 6 dB. For data measured at the 50-ft 2016 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication
20、is a violation of applicable law.TS-5a TP 98-3 AASHTO (15.2-m) position, the Lveh,refshall be extracted from the 50-ft (15.2-m) reference curve for comparison. For data measured at the 25-ft (7.6-m) position, the Lveh,refshall be extracted from the 25-ft (7.6-m) reference curve for comparison. (The
21、measurement positions are described in more detail in Section 10.) Table 1Reference Noise Curve Parameters for Position of Microphone50 ft (15.2 m) from the Center of the Lane, 5 ft or 12 ft (1.5 m or 3.7 m) above the Roadway Plane Reference Curve Coefficients for Reference Pavement Automobiles Medi
22、um Trucks Heavy Trucks Buses Motorcycles A 41.740807 33.918713 35.879850 23.479530 41.022542 B 0.223836 19.495961 20.306023 38.006238 7.333072 Table 2Reference Noise Curve Parameters for Position of Microphone25 ft (7.6 m) from the Center of the Lane, 5 ft (1.5 m) above the Roadway Plane Reference C
23、urve Coefficients for Reference Pavement Automobiles Medium Trucks Heavy Trucks Buses Motorcycles A 41.740807 33.918713 35.879850 23.479530 41.022542 B 6.223836 25.495961 26.306023 44.006238 13.333072 3.1.10. reference surfacethe reference surface is defined as the average pavement type from the FHW
24、A Traffic Noise Model (FHWA TNM) (FHWA-PD-96-009, FHWA-PD-96-010), measured in the Reference Energy Mean Emission Level (REMEL) study (FHWA-PD-96-008). All results shall be compared to the Reference Noise Curve based on the average pavement (dense-graded asphaltic concrete (DGAC) and portland cement
25、 concrete (PCC) combined found in the TNM vehicle noise emission level database REMELs (FHWA-PD-96-008). See Section 3.1.9 for reference curve coefficients. 3.1.11. reference vehicle sound level, Lveh,refthe sound level determined at the designated speed from the reference noise curve. 3.1.12. regre
26、ssion uncertaintythe uncertainty in the location of the true regression line for the linear regression analysis of sound level data as a function of speed. The procedure for calculating regression uncertainty is found in Section 14.1.4. 3.1.13. statistical isolated pass-by index (SIPI)SIPI is define
27、d as: SIPI = Lveh Lveh,refwhere Lvehis the measured vehicle sound level and Lveh,refis the reference vehicle sound level. The SIPI is the difference between sound levels representing two sets of data: (1) measured data for a single pavement type and single vehicle category, and (2) data representing
28、 the reference pavement and a single vehicle category. The SIPI can be used for the comparison of different pavements, for the assessment of the acoustical characteristics of a pavement over time, or for other comparison uses not specified. The procedure for calculating SIPI is found in Section 14.1
29、. 3.1.14. statistical isolated pass-by (SIP) methodthe measurement procedure designed to evaluate vehicle noise generated on different road surfaces by measuring the sound pressure level from isolated vehicles in existing traffic. The measurements are taken from a large number of vehicles operating
30、normally on the road. Results obtained using this procedure are compared to reference vehicle sound levels. 3.1.15. tire/pavement noisethe sound generated by the interaction of the tire with the pavement surface as it traverses the pavement. 2016 by the American Association of State Highway and Tran
31、sportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-5a TP 98-4 AASHTO 3.1.16. traffic noisethe overall noise emitted by multiple vehicles running over the road being evaluated. 3.1.17. vehicle categoryconsists of vehicles that have certain common features easy
32、to identify in the traffic stream, such as the number of axles and the size. The common features are assumed to correspond to similarities in their sound emission when driven under the same operating conditions. The vehicle categories in Table 3 are considered to be sufficient for description of the
33、 noise characteristics of road surfaces and are used in the SIP method. Table 3Vehicle Categories Vehicle Category Number of Axles, Number of Tires, Gross Vehicle Weight (examples) Automobiles 2 axles, 4 tires, and generally 9,900 lb (4500 kg) and 26,400 lb (12 000 kg) Buses 2 or 3 axles (designated
34、 for transportation of 9 or more passengers) Motorcycles 2 or 3 tires (with an open-air driver and/or passenger compartment) Notes: 1. The definitions for these vehicle categories are intended for U.S. applications, including the FHWA Traffic Noise Model (FHWA-PD-96-009, FHWA-PD-96-010) and its vehi
35、cle noise emission database (FHWA-PD-96-008). The vehicle category definitions can be found in those references as well as the FHWA highway noise measurement manual (FHWA-PD-96-046). 2. Only vehicles that clearly fall within any of the types described in this section shall be measured. Where there i
36、s any doubt in classifying a vehicle, the measurement for that vehicle shall be discarded from the study. 3.1.18. vehicle noisethe total noise from a vehicle, including a combination of noise generated by the tire/road interaction (tire/pavement noise), air turbulence, and the powertrain. 4. SUMMARY
37、 OF TEST METHOD 4.1. Measuring the Sound LevelIn the SIP method, the maximum A-weighted sound pressure levels of a statistically significant number of individual vehicle pass-bys are measured at a specified roadside location together with the vehicle speeds. Each measured vehicle is classified into
38、one of five categories: automobiles, medium trucks, heavy trucks, buses, and motorcycles. At a minimum, the automobile and heavy truck categories should be evaluated in order to determine the influence of each roadway surface (the other vehicle categories are optional). 4.2. Analysis of DataEach ind
39、ividual pass-by level, together with its vehicle speed, is recorded, and a linear regression of the maximum A-weighted sound pressure level versus the logarithm of the speed is calculated for each vehicle category. From this regression line, the measured vehicle sound level, Lveh, and regression unc
40、ertainty are determined at the designated speed. The measured sound level is called the measured vehicle sound level, Lveh. For each roadway surface or pavement type, the Lvehis calculated for each vehicle category. 4.3. Comparison of Data to ReferenceThe Lvehvalue is compared to the Reference Vehic
41、le Sound Level, Lveh,refusing the reference surface, both at the designated speed. The difference between the two values is calculated and reported as the Statistical Isolated Pass-by Index (SIPI). 5. SIGNIFICANCE AND USE 5.1. This test method provides an objective measure of the influence of road s
42、urfaces on vehicle noise at locations adjacent to a roadway and allows for the comparison of vehicle noise on roadways of varying surfaces by comparing measured sound levels to those representing the tire/pavement noise for a reference surface, thus allowing comparison of results across studies. 201
43、6 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-5a TP 98-5 AASHTO 5.2. Use of this method, in conjunction with other measurement methods, will increase the understanding of the influence of pavement on
44、noise and eventually be applicable to pavement design and selection. 5.3. The SIP procedure reports broadband A-weighted maximum sound pressure levels. While it is possible to measure one-third octave band levels in conjunction with the broadband levels, methods to analyze the one-third octave band
45、data are not included in this procedure. 5.4. In situations where it is not possible to measure single vehicle pass-by events without contamination from other vehicles, TP 99, Determining the Influence of Road Surfaces on Traffic Noise Using the Continuous-Flow Traffic Time-Integrated Method (CTIM),
46、 or another method that allows for measuring continuously flowing traffic should be applied. The appropriate measurement technique should be selected based on site and traffic conditions. The SIP method is preferred over TP 99 due to its ability to compare results across sites and/or studies. 5.5. T
47、he SIP test method may be used in conjunction with the on-board sound intensity (OBSI) method described in AASHTO TP 76 that measures the tire/pavement component of vehicle noise exclusively. 6. APPARATUS 6.1. Sound Level InstrumentationThe sound level meter (or equivalent measuring system) shall me
48、et the requirements of a Class 1 instrument according to IEC 61672-1. Note 1It is recommended to use a pressure response/random incidence microphone at grazing incidence (i.e., vertical orientation); see Figure 1. Figure 1Illustration of Directions for Microphone Orientation 6.2. WindscreensA windsc
49、reen that does not detectably influence the measured sound levels shall be used. 6.3. Frequency Analysis InstrumentationFrequency analysis of the measured sound using one-third octave band resolution is recommended, but not mandatory. The frequency range of 50 to 10 000 Hz (center frequencies of one-third octave bands) shall be covered. The one-third octave band filters shall conform to IEC 61260. Normal IncidenceGrazing IncidenceMicrophoneAxis 2016 by the American Association of State Highway and Transporta
