DK169797B1

DK169797B1 - Method and apparatus for measuring airborne sound in a building

Info

Publication number: DK169797B1
Application number: DK371287A
Authority: DK
Inventors: Robin Mackenzie
Original assignee: British Tech Group
Priority date: 1986-07-18
Filing date: 1987-07-16
Publication date: 1995-02-27
Also published as: DK371287D0; NO173203C; GB8716875D0; DK371287A; NO873006D0; NO873006L; GB2192716A; NO173203B; GB2192716B; GB8617566D0

Description

DK 169797 B1DK 169797 B1

Opfindelsen angår måling af luftbåren lyd i bygninger og især fremgangsmåder og apparater til vurdering af lydisoleringsegenskaberne for vægge og gulve.The invention relates to the measurement of airborne sound in buildings and in particular methods and apparatus for assessing the sound insulation properties of walls and floors.

I beskrivelsen har tekniske betegnelser de defi-5 nitioner og/eller betydninger, der er tilskrevet dem ifølge følgende liste.In the specification, technical terms have the definitions and / or meanings ascribed to them by the following list.

A-vejet lydtryk i Pascal: Det effektive lydtryk bestemt ved anvendelse af frekvensvejningsnetværk A, se I.E.C. publikation 651.A-weighted sound pressure in Pascal: The effective sound pressure determined by using frequency weighing network A, see I.E.C. publication 651.

10 A-vejet lydtryk i decibel: Lydtrykniveauet af det A-vejede lydtryk givet ved formlen10 A-weighted sound pressure in decibels: The sound pressure level of the A-weighted sound pressure given by the formula

LpA = 10 log(pA/PQ)2 15 Ækvivalent kontinuerligt A-vejet lydtryksniveau i decibel: Værdien af det A-vejede lydtryksniveau af en kontinuerlig, stabil lyd, der inden for et fastlagt tidsinterval T har samme middeltal for kvadratet på lydtrykkene som en betragtet lyd, hvis niveau varierer med 20 tiden. Det er givet ved formlen Γ i rt2 PA2(t) 1 LAeq,T “ 10 log[t2-t1 . J ~~2 dt z H p0 hvor 25 LAecf T er det ækvivalente kontinuerlige A-vejede lydtryksniveau i decibel bestemt over et tidsinterval T startende ved t1 og sluttende ved t2,LpA = 10 log (pA / PQ) 2 15 Equivalent continuous A-weighted sound pressure level in decibels: The value of the A-weighted sound pressure level of a continuous, stable sound having, within a specified time interval T, the same mean of the square of the sound pressure as a considered sound whose level varies by 20 time. It is given by the formula Γ in rt2 PA2 (t) 1 LAeq, T “10 log [t2-t1. J ~~ 2 dt z H p0 where 25 LAecf T is the equivalent continuous A-weighted sound pressure level in decibels determined over a time interval T starting at t1 and ending at t2,

Pq er referencelydtrykket, 20yPa, og p^(t) er det øjeblikkelige A-vejede lydtryk af lydsig-30 nalet.Pq is the reference sound pressure, 20yPa, and p ^ (t) is the instantaneous A-weighted sound pressure of the audio signal.

Måletidsintervallet er det tidsinterval, over hvilket det kvadrerede A-vejede lydtryk integreres og udjævnes.The target time interval is the time interval over which the squared A-weighted sound pressure is integrated and leveled.

Det udjævnede lydtryksniveau i et rum er ti gange 35 den almindelige logaritme til forholdet mellem kvadratet på rum- og tidsgennemsnittet af lydtrykket og kvadratet på referencelydtrykket, hvor rumgennemsnittet tages over 2 DK 169797 B1 rummet med undtagelse af de dele, hvor en lydkildes direkte stråling eller nærfeltet af grænseflader, vægge osv. øver indflydelse af betydning.The smoothed sound pressure level in a room is ten times the ordinary logarithm of the ratio of the square of the space and time average of the sound pressure to the square of the reference sound pressure, where the room average is taken over the room with the exception of the parts where a direct source or a sound source is used. the near field of interfaces, walls, etc. exerts a significant influence.

Denne størrelse betegnes med L, hvor 5 2 2 2 P-I + p2 +..........pn L = 10 log —---5-— np0 hvor p., p9,.....p er de effektive lydtryk på n forskellige I Μ Π 10 steder i rummet, Pø = 20uPa er referencelydtrykket.This size is denoted by L, where 5 2 2 2 PI + p2 + .......... pn L = 10 log —--- 5-— np0 where p., P9, ..... p are the effective sound pressures at n different I Μ Π 10 places in the room, P0 = 20uPa is the reference sound pressure.

Den A-vejede niveauforskel er forskellen i A-ve-jede lydniveauer udjævnet i rum og tid frembragt i to rum af en eller flere lydkilder i et af disse. Størrel-15 sen betegnes med D^, hvor DA = LA,1 “ LA, 2 hvor L- - er det gennemsnitlige lydtryksniveau i kilde-A/ i 20 rummet, og ^ er det gennemsnitlige lydtryksniveau i modtagerummet. Den standardiserede niveauforskel er niveauforskellen svarende til en referenceværdi for efterklangstiden i modtagerummet. Denne størrelse er betegnet med D _, hvor n?' 25The A-weighted level difference is the difference in A-weighted sound levels leveled in space and time produced in two rooms by one or more sound sources in one of these. The magnitude is denoted by D ^, where DA = LA, 1 "LA, 2 where L- - is the average sound pressure level in the source A / in the room, and ^ is the average sound pressure level in the receiver room. The standardized level difference is the level difference corresponding to a reference value for the reverberation time in the receiver room. This size is denoted by D _, where n? ' 25

Dn<p = ° t 10 log(T/T0) dBDn <p = ° t 10 log (T / T0) dB

hvor D er niveauforskellen, T er efterklangstiden i modtagerummet, Tg er referenceefterklangstiden. Por op-30 holdsrum er Tg givet vedwhere D is the level difference, T is the reverberation time in the receiver room, Tg is the reference reverberation time. For up to 30 team rooms, Tg is given

Tg = 0,5sTg = 0.5s

Standardiseringen af niveauforskellen til en ef-35 terklangstid på 0,5s tager hensyn til, at efterklangstiden i opholdsrum med møbler er fundet til, næsten uafhængigt af volumenet og af frekvensen, at være lig DK 169797 Bl 3 med 0,5s. Med denne standardisering er DnT afhængig af lydtransmissionsretningen, hvis de to rum har forskellige volumener.The standardization of the level difference to an after-sound time of 0.5s takes into account that the reverberation time in living rooms with furniture has been found to be almost independent of the volume and frequency, equal to DK 169797 Bl 3 by 0.5s. With this standardization, DnT is dependent on the sound transmission direction if the two compartments have different volumes.

Standardiseringen af niveauforskellen til efter-5 klangstiden i modtagerummet på Tg = 0,5s er ækvivalent med standardisering af niveauforskellen med hensyn til et ækvivalent absorptionsareal påThe standardization of the level difference to the post-echo time in the receiver space of Tg = 0.5s is equivalent to standardizing the level difference with respect to an equivalent absorption area of

Ag = 0,32VAg = 0.32V

10 hvor Ag er det ækvivalente absorptionsareal i kvadratmeter, og V er volumenet af modtagerummet i kubikmeter. Fremgangsmåden til måling af isolering for luftbåren lyd i bygninger involverende feltmålinger mellem rummene 15 i henhold til frekvensen er standardiseret i I.S.O.10 where Ag is the equivalent absorption area in square meters and V is the volume of the receiving space in cubic meters. The method of measuring insulation for airborne sound in buildings involving field measurements between rooms 15 according to frequency is standardized in I.S.O.

140/4. 1978 Acoustics - Measurement of sound insulation in buildings and of building elements; Part 4: Field measurements of airborne sound insulation between rooms.140/4. 1978 Acoustics - Measurement of sound insulation in buildings and of building elements; Part 4: Field measurements of airborne sound insulation between rooms.

Disse procedurer er lange og komplicerede, og 20 der har derfor rejst sig et behov for en kort prøvemetode, der kan tilvejebringe et estimat af enkelttalsvurderingen.These procedures are lengthy and complicated, and therefore a short test method has emerged that can provide an estimate of the single-digit assessment.

Fra GB-patentskrift nr. 1.472.713 kendes en fremgangsmåde til måling af akustisk isolering, hvor 25 der ved måling af lydtransmission mellem to rum benyttes en sender, hvis lydeffektniveau udviser en ulineær variation som funktion af frekvensen svarende til et A-vejet lydtryk. Denne variation forløber uden spidser.GB patent 1,472,713 discloses a method for measuring acoustic insulation, where a transmitter whose sound power level exhibits a nonlinear variation as a function of the frequency corresponding to an A-weighted sound pressure is used in measuring sound transmission between two rooms. This variation proceeds without spikes.

Ifølge opfindelsen tilvejebringes en fremgangs-3^ måde til måling af lydtransmissionskarakteristikkerne for bygningselementer mellem to rum af en bygning, omfattende trinnene at opstille en lydkilde i det første af de nævnte to rum og måle lydniveauet i det andet af de to rum ved et antal forskellige frekvenser, hvilken 33 fremgangsmåde er ejendommelig ved, at senderens lydenerginiveau og den relative følsomhed af modtageren udviser en forud fastlagt ulineær variation med hensyn til frekvens, hvilken variation udviser mindst én spids.According to the invention, there is provided a method for measuring the sound transmission characteristics of building elements between two compartments of a building, comprising the steps of setting up a sound source in the first of said two compartments and measuring the sound level in the second of the two compartments by a number of different frequencies which are characterized in that the transmitter's sound energy level and the relative sensitivity of the receiver exhibit a predetermined nonlinear frequency variation which exhibits at least one peak.

4 DK 169797 B14 DK 169797 B1

Det har vist sig fordelagtigt, at den spektrale fordeling følger en specifik kurveform, hvor denne har mindst én spids.It has been found advantageous that the spectral distribution follows a specific waveform where it has at least one peak.

Fremgangsmåden er indrettet til at anvendes af 5 bygningskontrolinspektører eller personer, der varetager en lignende rolle, for at tillade udførelse af en hurtig og enkel prøvning af isolationen for luftbåren lyd mellem rummene.The method is designed to be used by 5 building control inspectors or persons performing a similar role to allow a quick and simple test of the airborne sound insulation between the rooms.

Opfindelsen angår også et apparat til måling iføl-10 ge fremgangsmåden af lydtransmissionskarakteristikker for bygningselementer mellem to rum i en bygning, og omfattende et filter med ulineær frekvensoverføringskarakteristik, hvilket apparat er ejendommeligt ved, at den ulineære frekvensoverføringskarakteristik udviser 15 mindst én spids.The invention also relates to an apparatus for measuring the method of sound transmission characteristics of building elements between two compartments of a building, and comprising a filter with non-linear frequency transmission characteristic, characterized in that the non-linear frequency transmission characteristic has at least one tip.

Opfindelsen forklares i det følgende nærmere under henvisning til tegningen, på hvilken fig. 1 skematisk viser udformningen af et apparat til måling i et lydkilderum, 2ø fig. 2 skematisk udformningen af et apparat til måling i et modtagerum, fig. 3 et effektniveauspektrum for en kombineret væg/gulvstøjkilde, fig. 4 et effektniveauspektrum for en vægstøj-25 kilde, og fig. 5 et effektniveauspektrum for en gulvstøjkilde.The invention will now be explained in more detail with reference to the drawing, in which: FIG. 1 is a schematic representation of the design of an apparatus for measuring in a sound source room; FIG. 2 is a schematic representation of an apparatus for measuring in a receiving room; FIG. 3 shows a power level spectrum for a combined wall / floor noise source; FIG. 4 is a power level spectrum for a wall noise source; and FIG. 5 is a power level spectrum for a floor noise source.

Fremgangsmåden ifølge opfindelsen er baseret på bestemmelsen af den A-vejede lydniveauforskel mellem 2Q op til hinanden stødende rum uden hensyn til transmissionsvejene.The method according to the invention is based on the determination of the A-weighted sound level difference between 2Q adjacent spaces, regardless of the transmission paths.

Lydniveaudifferensen med henblik på denne fremgangsmåde er den, der opnås fra de rum- og tidsudjævnede A-vejede lydniveauer i henholdsvis kilderummet SR og 25 modtagerummet RR som følge af funktionen af en speciel lydkilde i kilderummet. I tilfælde af umøblerede rum må der tilføjes absorption i både kilderummet og modtagerummet for at minimere spektral ubalance forårsaget af variationer i rumabsorptionen ved forskellige frekvenser.The noise level difference for the purpose of this method is that obtained from the space- and time-smoothed A-weighted sound levels in the source room SR and the receiver room RR, respectively, as a result of the function of a particular sound source in the source room. In the case of unfurnished spaces, absorption must be added in both the source space and the receiver space to minimize spectral imbalance caused by variations in space absorption at different frequencies.

5 DK 169797 B15 DK 169797 B1

Ifølge en foretrukken udførelsesform for opfindelsen er lydkilden, der anvendes til lydniveaudifferensmålingerne en kombination af højttaler, forstærker og generator for tilfældig støj. Det maksimalt til rå-5 dighed stående oktavbånd-lydeffektniveau for tilfældig støj falder inden for de skyggede grænser i fig. 3 for en kombineret vsg/gulvkilde og i fig. 4 og 5 for særskilte væg- og gulvkilder. Højttalerindeslutningens dimensioner var indskrænket til 500 mm højde x 350 mm 1Q bredde x 2500 mm dybde ±10%. Den maksimale bredbånds-lydeffektudgang er 120 dB over 10 ^W. Højttaleren er udstyret med eftergivende puder på bunden af kabinettet for at minimere transmissionen af højttalervibrationer til gulvet. Ideelt skal lydkilden kunne tændes og sluk-15 kes ved fjernbetjening ved hjælp af FM-sender/modtager-kredsløb.According to a preferred embodiment of the invention, the sound source used for the sound level difference measurements is a combination of loudspeaker, amplifier and random noise generator. The maximum available octave band sound power level for random noise falls within the shaded limits of FIG. 3 for a combined vsg / floor source and in FIG. 4 and 5 for separate wall and floor sources. The dimensions of the speaker enclosure were limited to 500 mm height x 350 mm 1Q width x 2500 mm depth ± 10%. The maximum broadband audio output is 120 dB over 10 ^ W. The speaker is equipped with resilient pads on the bottom of the cabinet to minimize the transmission of speaker vibrations to the floor. Ideally, the audio source should be able to be turned on and off by remote control using FM transmitter / receiver circuits.

En absorbentpakke omfattende tre polyetherskum-plader, 30 kg/m , der måler 1000 mm x 500 mm x 50 mm, anvendes i kilde- og modtagerummene, dvs. tre paneler 20 i hvert rum, for at kompensere for operatørens tilstedeværelse.An absorbent package comprising three polyether foam sheets, 30 kg / m measuring 1000 mm x 500 mm x 50 mm, is used in the source and receiver compartments, ie. three panels 20 in each compartment to compensate for the presence of the operator.

Under målingerne lukkes alle døre og vinduer i rummene, der er under prøve.During the measurements, all doors and windows in the rooms under test are closed.

Lydniveaumåleren kalibreres med en hulrumskali-25 brator i overensstemmelse med fabrikantens instruktioner, før og efter målingerne foretages for hvert par rum. Efter kalibrering indstilles lydniveaumåleren til A-vej-ning for resten af prøveproceduren. Hvis rummet er umøbleret, rejses en absorbentskærm AS magen til den i fig.The sound level meter is calibrated with a cavity calibrator according to the manufacturer's instructions, before and after the measurements are made for each pair of compartments. After calibration, the sound level gauge is set to A-weighing for the remainder of the test procedure. If the room is unfurnished, an absorbent screen AS similar to that of FIG.

30 1 viste udformning. Denne udformning anvendes, når ope ratøren er til stede i kilde- eller modtagerummet. Når operatøren O forlader kilderummet, indstilles skærmen, som vist i fig. 2, for at kompensere for den af operatøren tilvejebragte absorption, medens han er til stede 35 i rummet. Det er vigtigt, at ingen anden person end operatøren er til stede i prøverummene, medens målingen 6 DK 169797 B1 udføres. Lydkilden placeres på gulvet i den side af rummet, der ligger over for skillevæggen, med højttalerens forside vendende ind imod rummet under en vinkel på 45°. Hvis lydkildeudstyret er udstyret med særskilte spek-5 trer for vægge og for gulve, vælges det behørige spektrum. Ved afprøvning af gulve vælges det nederste rum som kilderum. Lydudgangskontrollen skal indstilles, således at der frembringes et A-vejet lydniveau ved mindst 10 dB over baggrundslydniveauet.30 1. This configuration is used when the operator is present in the source or receiver space. As the operator O leaves the source room, the screen is set as shown in FIG. 2 to compensate for the absorption provided by the operator while being present in the room. It is important that no person other than the operator is present in the test rooms while the measurement 6 DK 169797 B1 is being performed. The sound source is placed on the floor in the side of the room opposite the partition, with the front of the speaker facing towards the room at an angle of 45 °. If the sound source equipment is equipped with separate spectra for walls and floors, the appropriate spectrum is selected. When testing floors, the lower room is selected as the source room. The audio output control must be set so as to produce an A-weighted sound level at least 10 dB above the background sound level.

10 En måling foretages indledningsvis i modtagerum met for at tillade sammenligning med baggrundsstøjniveauet. Hvis lydniveauet i modtagerummet er mindre end 10 dB over baggrundsstøjen, anvendes der for modtage-rumniveauet en korrektion i henhold til tabel 2. Den 15 integrerende lydmåler holdes en armlængde ud fra operatøren, der står så nær ved midten af rummet som muligt. Mikrofonen skal drejes fire gange over 360°, idet armen bevæges op og ned i en rolig bevægelse under gennemløbet. De fire omdrejninger skal fuldendes inden for en 20 samlet tid på ca. 30 sekunder. Det kan være nødvendigt at forlænge måleperioden, når der anvendes en ikke-inte-grerende lydniveaumåler. LAeg(30 sekunder) noteres og tages som værdien for 2· En måling magen til den i modtagerummet foretagne udføres i kilderummet, hvilket 25 giver LA v10 A measurement is initially made in the receiving room to allow comparison with the background noise level. If the noise level in the receiver room is less than 10 dB above the background noise, a correction for the reception room level is used according to Table 2. The 15 integral sound meter is kept an arm's length from the operator as close to the center of the room as possible. The microphone must be rotated four times over 360 °, moving the arm up and down in a gentle motion during the passage. The four turns must be completed within a total of 20 approx. 30 seconds. It may be necessary to extend the measurement period when using a non-integrating sound level meter. A note (30 seconds) is noted and taken as the value for 2 · A measurement similar to that in the receiving room is performed in the source room, which gives 25 v

Lydniveauforskellen D^ mellem kilde- og modtagerum beregnes derpå. Den behørige værdi for Dnrpw læses direkte fra tabellen 1, som er fundet empirisk.The noise level difference D ^ between source and receiver rooms is then calculated. The proper value for Dnrpw is read directly from Table 1, which has been found empirically.

Selv om opfindelsen er beskrevet under henvis-30 ning til et sendeapparat, der har et defineret transmissionsspektrum, og en modtager med en i hovedsagen flad karakteristik, er det klart for en fagmand, at tilsvarende resultater kan opnås med en sender med en flad transmissionskarakteristik og modtager med en ka-35 rakteristik, der er komplementær til de i fig. 4 og 5 viste transmissionskarakteristikker, eller både sender og modtager kan have komplementære ikke-lineære karakteristikker til opnåelse af den samme samlede virkning.Although the invention is described with reference to a transmitter having a defined transmission spectrum and a receiver having a substantially flat characteristic, it is clear to one skilled in the art that similar results can be obtained with a transmitter having a flat transmission characteristic and receiver having a characteristic complementary to those of FIG. 4 and 5, or both transmitter and receiver may have complementary non-linear characteristics to achieve the same overall effect.

DK 169797 B1 7DK 169797 B1 7

Tabel 1 D D π nTwTable 1 D D π nTw

Tilstand af modtagerum Møbleret Umøbleret + Vægge Gulve 05 tilføjet absorbent 35 32 38 37 36 33 39 38 37 34 40 39 38 35 41 40 10 39 36 42 41 40 37 42 42 41 38 43 42 42 39 44 43 43 40 45 44 15 44 41 45 45 45 42 46 46 46 43 47 47 47 44 48 47 48 45 49 48 20 49 46 50 49 50 47 50 49 51 48 51 . 50 52 49 52 51 53 50 53 52 25 54 51 54 53 55 52 54 54 56 53 55 55 57 54 56 56 58 55 57 57 30 59 56 57 57 60 57 58 58 61 58 59 59 62 59 60 60 63 60 61 61 35 64 61 62 62 65 62 63 63 8 DK 169797 B1Condition of reception room Furnished Unfurnished + Walls Floors 05 added absorbent 35 32 38 37 36 33 39 38 37 34 40 39 38 35 41 40 10 39 36 42 41 40 37 42 42 41 38 43 42 42 39 44 43 43 40 45 44 15 44 41 45 45 45 42 46 46 46 43 47 47 47 44 48 47 48 45 49 48 20 49 46 50 49 50 47 50 49 51 48 51. 50 52 49 52 51 53 50 53 52 25 54 51 54 53 55 52 54 54 56 53 55 55 57 54 56 56 58 55 57 57 30 59 56 57 57 60 57 58 58 61 58 59 59 62 59 60 60 63 60 61 61 35 64 61 62 62 65 62 63 63 8 DK 169797 B1

Tabel 2Table 2

Forskel mellem lydtryk- Korrektion, der skal trækniveau målt med lydkilde kes fra lydtrykniveauet, arbejdende og baggrunds- der måles med lydkilde ar-5 niveau alene bejdende for at opnå lyd trykniveauet som følge af lydkilden alene 3 3 10 4 til 5 2 6 til 9 1 15Difference between sound pressure - Correction to be drawn level measured with sound source from the sound pressure level, working and backgrounds measured with sound source ar-5 level only working to achieve the sound pressure level due to the sound source alone 3 3 10 4 to 5 2 6 to 9 1 15

Claims

9 DK 169797 B1

A method for measuring the sound transmission characteristics of building elements between two compartments (SR, RR) in a building, comprising setting up an audio source (LS) in the first (SR) of the two compartments and measuring the sound level in the second ( RR) of the two compartments at a number of different frequencies, characterized in that the sound power level of the transmitter and the relative sensitivity of the receiver exhibit a predetermined nonlinear variation as a function of frequency, which variation exhibits at least one peak.

2. A method for measuring the sound transmission characteristics of building elements between two rooms. in a building according to claim 1, characterized in that the predetermined non-linear variation for combined floor and wall measurements falls substantially within those in the drawing of FIG. 3 specified limits.

A method for measuring the sound transmission characteristics of building elements between two compartments 20. a building according to claim 1, characterized in that the nonlinear variation for wall measurements falls substantially within those of FIG. 4 specified limits.

Method for measuring the sound transmission characteristics of building elements between two compartments in a building according to claim 1, characterized in that the predetermined nonlinear variation for floor measurements falls substantially within those of FIG. 5 specified limits.

Method for measuring the sound transmission characteristics of building elements between two rooms in a building according to any one of the preceding claims, characterized in that a correction factor is added to the measurements when the sound level in the receiving room is 35 less than 10 dB above the background sound level. 10 DK 169797 B1

Apparatus for measuring according to the method of claim 1 of sound transmission characteristics for building elements between two compartments (SR, RR) in a building, comprising a filter with non-linear frequency transmission characteristic, characterized in that the non-linear frequency transmission characteristic exhibits at least one tip.