1、Designation: E2963 15Standard Test Method forLaboratory Measurement of Acoustical Effectiveness ofShip Noise Treatments Laboratory Measurement ofAcoustical Effectiveness for Marine Bulkhead and DeckTreatments1This standard is issued under the fixed designation E2963; the number immediately following
2、 the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.INTRODUCTIONThis test method is d
3、esigned to measure the acoustical effectiveness of treatments that are intendedto reduce airborne noise on ships. Such treatments would be applied to compartment structuralpartitions such as bulkheads, decks, and side shells. To fully characterize the acoustical performanceof a treatment, five param
4、eters must be assessed: transmission loss, radiation efficiency, acceptance,absorption, and damping. This test method focuses on the assessment of the first three, and providesfor convenient assessments of absorption and damping. Tests discussed in this method are based onthe Test Method E90 setup a
5、nd procedure. This test method is not intended to be a replacement of TestMethod E90; conversely, this method builds on the E90 method that is now well established. Similarly,this test method does not replace absorption testing discussed in Test Method C423, nor dampingtesting discussed in Test Meth
6、od E756, though for reasons of convenience this method can be used tomake approximate assessments of how different treatments may impact these parameters.1. Scope1.1 This test method covers the laboratory measurement ofthe acoustical effectiveness of treatments installed on shipbulkheads, decks, and
7、 side shells. Measurements are focusedon assessing changes in transmission loss, radiation efficiency,and acceptance that occur when treatments are applied. Mea-surements of changes to absorption and damping are addressedin Appendix X1 and Appendix X2, respectively.1.2 The values stated in SI units
8、are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practic
9、es and determine the applica-bility of regulatory limitations prior to use.1.4 Any material that is to be installed on a marine divisionmust meet appropriate fire, combustibility, and other applicableSOLAS, USCG, IMO, Navy, or other required non-acousticalstandards and specifications. See Appendix X
10、3 for additionalinformation.2. Referenced Documents2.1 ASTM Standards:2C423 Test Method for SoundAbsorption and SoundAbsorp-tion Coefficients by the Reverberation Room MethodE634 Practice for Sampling of Zinc and Zinc Alloys bySpark Atomic Emission SpectrometryE90 Test Method for Laboratory Measurem
11、ent of AirborneSound Transmission Loss of Building Partitions andElementsE756 Test Method for Measuring Vibration-Damping Prop-erties of Materials2.2 ANSI Standards:3ANSI S1.4-1983 (R2006) Specification for Sound LevelMetersANSI S1.6-1984 (R2011) Preferred Frequencies, Frequency1This test method is
12、under the jurisdiction ofASTM Committee E33 on Buildingand Environmental Acoustics and is the direct responsibility of SubcommitteeE33.03 on Sound Transmission.Current edition approved Dec. 1, 2015. Published December 2015. Originallyapproved in 2014. Last previous edition approved in 2014 as E2963
13、14. DOI:10.1520/E296315.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Sta
14、ndards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1Levels, and Band Number for Acoustical MeasurementsANSI S1.8-1989 (R2011) ,Reference Quantities
15、for Acous-tical LevelsANSI S1.11-2004 (R2009) Specification for Octave-Bandand Fractional-Octave-Band Analog and Digital FiltersANSI S1.43-1997 (R2007) Specifications for Integrating-Averaging Sound Level Meters2.3 ISO Stadnard:4ISO 16063-1:1998 , Methods for the Calibration of Vibrationand Shock Tr
16、ansducers3. Terminology3.1 Definitions: The following terms used in this testmethod have specific meanings that are defined in TerminologyE634.airborne soundaverage sound pressure levelbackground noisedampingdecibeldiffuse sound fielddirect sound fieldflanking transmissionleveloctave bandreceiving r
17、oomreverberant sound fieldreverberation roomsound levelsound pressuresound pressure levelsource roomunit3.1.1 As defined in Test Method E90 transmission loss is thedifference in decibels between the average sound pressurelevels in the reverberant source and receiving rooms, plus tentimes the common
18、logarithm of the ratio of the area of thecommon partition to the sound absorption in the receivingroom (see Eq 4).3.1.2 As defined in Test Method E90 sound absorption of aroom in a specified frequency band is the hypothetical area ofa totally absorbing surface without diffraction effects which, ifit
19、 were the only absorbing element in the room, would give thesame sound decay rate as the room under consideration.3.2 Definitions of Terms Specific to This Standard:3.2.1 acceptance, na measure of the vibration velocitylevel induced in a structure that is exposed to a diffuse soundfield composed of
20、one or more frequencies (see Eq 6).3.2.2 acoustical effectiveness, na measure of the change ina particular acoustical parameter that is created by the additionof a material to the base structure.3.2.3 radiation effciency, na measure relating the soundpressure level in a diffuse sound field that is p
21、roduced by avibrating structural surface, referenced to a specified vibrationvelocity level, when that surface is moving in an oscillatorymotion at one or more frequencies (see Eq 8).3.2.4 test or base structure, nThe structure representinga bulkhead, deck, or shell of a ship.3.2.4.1 DiscussionThe b
22、ase structure is typically con-structed with steel or aluminum stiffened plating, though otherconstruction types are possible. This is the structure to whichtreatments are applied.3.3 Symbols:A = room constant, m2S = area of partition (structure under test), m2a = acceleration, m/s2c = speed of soun
23、d in air, m/sdB = decibelsf = frequency, Hzp = pressure, Pav = velocity, m/sLa= vibration acceleration level, dB re: 10 m/s2Lp= sound pressure level, dB re: 20 Pa. Lv velocitylevel, dB re: 10 nm/s (that is, 10-8m/s)L= acceptance in decibels referenced to 20 Pa/10 nm/sL= radiation efficiency in decib
24、els referenced to 20Pa/10 nm/sTL = transmission loss in decibelsX = change in the quantity “X” between treated andnon-treated test cases = sound absorption coefficient = loss factor, (no dimensions) = density, kg/m33.4 All levels expressed in decibels have a reference quan-tity. A level expressed in
25、 decibels is 10 times the commonlogarithm of the ratio of a squared quantity divided by asquared reference quantity. For example, the reference quantityfor sound pressure level is 20 micropascals. The abbreviatedlevel is written as dB re: 20 Pa4. Summary of Test Method4.1 The effectiveness of a give
26、n treatment is determined bycomparing the acoustical properties of a given structure withand without the treatment applied. Measurements are firstperformed on a baseline test structure (that is, without thetreatment in place). The treatment is then added to the structureand tests are repeated. The d
27、ifferences in acoustical parametersbetween the treated and non-treated structures determine theacoustical effectiveness of the treatment.4.2 The general test setup discussed in Test Method E90shall be used. Two adjacent reverberation rooms are arrangedwith an opening between them in which a test par
28、tition isinstalled.4.3 Transmission loss, acceptance, and radiation efficiency(as well as absorption and damping) are all functions offrequency, and measurements are made in a series of frequencybands.4.4 For measurement of transmission loss, Test Method E90shall be used to test both the treated and
29、 non-treated structures.Fig. 1 presents a schematic diagram of the test setup, forreference purposes.4.5 For the measurement of acceptance, the same test setupdiscussed in Test Method E90 is used with accelerometersattached to the test structure. An approximately diffuse sound4Available from Interna
30、tional Organization for Standardization (ISO), 1, ch. dela Voie-Creuse, CP 56, CH-1211 Geneva 20, Switzerland, http:/www.iso.org.E2963 152field is produced in the source room; the space- and time-averaged sound pressure levels are measured in this room. Thevibration levels of the test structure are
31、simultaneously mea-sured to produce a space- and time-averaged vibration level ofthe structure (see Fig. 2). These quantities (sound pressurelevel and test structure vibration level) are combined todetermine the acceptance for the test structure, as shown inSection 13.4.6 For the measurement of radi
32、ation efficiency, the sametest setup discussed in Test Method E90 is used. Accelerom-eters are located on the test structure along with an electro-mechanical vibration exciter. The vibration exciter drives thestructure, which then radiates sound into the receiver room.The sound field produced in thi
33、s room is considered to bediffuse. The rooms space- and time-averaged sound pressurelevels are measured, as well as the structures space- andtime-averaged vibration level (see Fig. 3). These quantities,along with the sound absorption in the receiving room and thearea of the specimen, are combined to
34、 determine the radiationefficiency for the test structure, as shown in Section 13.4.7 Room absorption measurements are necessary to calcu-late transmission loss and radiation efficiency. The change inroom absorption between the treated and non-treated tests willbe directly related to any absorption
35、provided by the treatment.While treatment absorption measurements are formally cov-ered by Test Method C423 it is convenient to use the measuredroom absorption from transmission loss and radiation effi-ciency tests to determine the effect of the treatment onabsorption. This is discussed in more deta
36、il in Appendix X1.These measurements shall not replace measurements describedin Test Method C423 as the results would be different.However, they can provide a useful and convenient indicationof the absorption of a treatment, which may have sufficientaccuracy for engineering applications (see Appendi
37、x X1).4.8 The effect of a treatment on the structures total dampingloss factor formally requires a different test setup than thatdescribed in Test Method E90. However, the same structuresused for the tests described above can be used to estimatedamping effectiveness. Options for measuring damping ar
38、ediscussed in more detail in Appendix X2.This image is for illustrative purposes only.FIG. 1 Illustration showing the conceptual setup for transmission loss testing (based on Test Method E90)This image is for illustrative purposes only.FIG. 2 Illustration Showing the Conceptual Setup for Acceptance
39、Testing (Note the Similarities to Fig. 1)E2963 1535. Significance and Use5.1 To fully understand the effects of a given treatment, fiveacoustical factors (transmission loss, acceptance, radiationefficiency, absorption, and damping) must be characterized.For example, only knowing the effect of a give
40、n treatment ontransmission loss will not allow the acoustical designer orengineer to assess its impacts on propagation of vibration(among other effects), which is an important path to considerfor large machinery items and propeller excitation.5.2 It is necessary to have a common definition of acoust
41、icalperformance and test procedure to determine all five acousticalfactors for ships treatments so that the performance ofdifferent treatment types, as well as the same treatment typefrom different manufacturers, can be compared.5.3 In some cases, particularly for damping treatments, theeffect of th
42、e treatment will be dependent on the non-treatedstructures material and geometry and other non-acousticfactors such as environmental conditions (that is, temperature).To fully characterize a treatment it may be necessary to test arange of base constructions. For reasons of practicality,convenience,
43、or economy, it may be sufficient to test only oneto three constructions to achieve an understanding of thematerial performance in a range of practical situations. Addi-tional discussion is provided in Annex A1.6. Test Apparatus6.1 The room requirements of Test Method E90 shall beused for the testing
44、 of transmission loss, acceptance, andradiation efficiency. Special attention may be needed whentesting the treated structure to meet the signal-to-noise ratio perTest Method E90.6.2 Where the test structure is smaller than the openingbetween the source and receiver rooms, a filler wall shall becons
45、tructed as described in Test Method E90. Meeting thetransmission loss requirements for this filler wall shall consti-tute meeting related requirements for acceptance and radiationefficiency.6.3 The structure shall be constructed to be representative ofactual bulkhead, deck, or shell structure to whi
46、ch the treatmentwill be applied. Often, a single treatment can be applied tomany different structures and construction types; therefore, notall constructions can be practically tested. In such cases it isrecommended that one to three referencebulkheads be tested,as discussed in Annex A1, to establis
47、h a baseline materialperformance to which other materials can be readily compared.If treatment effectiveness is expected to change significantlywith different bulkhead constructions then additional construc-tions shall be tested to better define the performance of thematerial.6.4 Treatments shall be
48、 applied to the test structure as theywould be in an actual ship installation. This includes the use ofspecial mounting hardware or edge treatments, as applicable.6.5 Aging of SpecimensTreatments that incorporate mate-rials for which there is a curing process shall age for a sufficientinterval befor
49、e testing, as recommended by the manufacturer.In these cases, it may be convenient and practical to useseparate test structures of identical construction to test thetreated and non-treated conditions.7. Test Signal Sources7.1 Signal SpectrumThe sound and vibration signals usedfor these tests shall be random noise having a continuousspectrum within each test frequency band.7.2 Sound SourcesSound is generated in the rooms usingloudspeaker systems. The requirements for sound sourcesdefined in Test Method E90 shall be followed.7.3 Vibration SourcesA
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