PICC acoustic system

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TAYLOR’S UNIVERSITY BUILDING SCIENCE II PROJECT 1 __________________________________________________________________________________ Building Science 2 ARC 3413 / BLD 61303 Case study on Acoustic Design of Putrajaya International Convention Centre (PICC) Tutor: Mr. Azim Sulaiman Submission date : 2 nd of May 2017 Student name and ID: Lee Pui San 0319089 Beh NianZi 0319445 Eng Shi Yi 0317849 Fong Tze Ying 0324073 Gary Yeow Jinn Sheng 0318797 Lynette Law Yong Yi 0317761 Liu Jyue Yow 1007P74080 Fatemehalsadat Fattahhosseini 0318452

Transcript of PICC acoustic system

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TAYLOR’S UNIVERSITY

BUILDING SCIENCE II

PROJECT 1

__________________________________________________________________________________

Building Science 2 ARC 3413 / BLD 61303

Case study on Acoustic Design of Putrajaya International

Convention Centre (PICC)

Tutor: Mr. Azim Sulaiman

Submission date : 2nd of May 2017

Student name and ID:

Lee Pui San 0319089

Beh NianZi 0319445

Eng Shi Yi 0317849

Fong Tze Ying 0324073

Gary Yeow Jinn Sheng 0318797

Lynette Law Yong Yi 0317761

Liu Jyue Yow 1007P74080

Fatemehalsadat Fattahhosseini 0318452

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Table of content

Topic Page 1.0 Abstract 1

2.0 Acknowledgement 2

3.0 Introduction

-3.1 Historical Background

-3.2 Programmes

-3.3 Architectural Design

-3.4 PICC Master Plans

3

4

4-5

5-6

7-9

4.0 Sound Source

-4.1 Speech Intelligibility

-4.2 Sound Reinforcement System (Sound Amplifier)

10

11-12

13-14

5.0 Sound Path

-5.1 Echoes

-5.2 Focusing

-5.2 Room Shape

15

15-16

17

18-19

6.0 Material used in sound acoustic system

-6.1 Wall

-6.1.1 Perforated Acoustic Panel

-6.1.2 Acoustical Fabric

-6.1.3 Timber Frame

-6.1.4 Wall Acoustic Panel

-6.1.5 Translator Room

-6.2 Ceiling

-6.3 Floor

-6.4 Seating

-6.5 Door

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21

22-24

25

26-27

28-29

30-32

33-34

35-36

37-39

40-42

7.0 Conclusion 43

8.0 References 44-45

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1.0 Abstract

In this assignment, we , a group of 8 students are required to conduct a case study on a local

auditorium. They have to carry out a site visit to their respective chosen building to observe and

record their findings into a report.

Throughout the assignment, we are able to understand the importance of sound acoustic

system as a significant role in an auditorium. Meanwhile, we can illustrate our ideas and

understanding after on-site findings as well as references on books and online resources.

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2.0 Acknowledgement

First of all, we would like to address our appreciation to Mr Azim for his guidance throughout

the process of this project. We are able to improve our works with the time Mr Azim had spent

with us. We were given a precious chance to visit Malaysian Philharmonic Orchestra for

in-depth explanations from professionals.

Also, we would like to thank Ar Edwin had gave us lessons during lecture which helpful for our

study. From the given slides, we are able to realize the characteristic of sound

comprehensively.

Last but not least, we are truly grateful that Putrajaya International Conventional Centre office

gave us this opportunity to visit the Plenary Hall to observe and analyse the sound acoustic

system of the hall. The tour guide was generous to provide us as much informations as she

could for us.

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3.0 Introduction

Figure 3.0.1 Front view of PICC

The Putrajaya International Convention Centre is the main convention centre in Putrajaya,

Malaysia. This building is located on the top of Taman Puncak Selatan in Precinct 5. PICC

receives a yearly average of more than 230,000 delegates and 15,000 visitors around the world

since 2006.

Architect : Hijjas Kasturi Associates / Amir Hamzah

Client : Jabatan Perdana Menteri

Built Area : 135,000 sqm

Commission Year : 2000

Design : 2001

Construction : 2001 - 2003

Occupancy : 2003

Total Floor Area : 135,000 sqm

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3.1 Historical Background

Construction of the convention centre began in 2001 and finished in April 2003. The first

conference held in PICC was the 10th Islamic Summit organised by the Organisation of Islamic

Cooperation (OIC) in October of the same year. In October 2004, the Putrajaya Convention

Centre was officially renamed to the Putrajaya International Convention Centre or PICC. It is a

precinct landmark, and was designed by Malaysia’s fourth Prime Minister, Tun Dr. Mahathir Bin

Mohamad.

3.2 Programmes

Figure 3.2.1 Facilities and services in PICC

A low-slung bridge through tropical gardens connects to the Plenary Hall, one of the most

impressive of the 5 building modules. It can conveniently accommodate 3,500 people in a

theatre set up for convention meetings or special events. It is also equipped with a permanent

stage, dressing rooms and a VIP lounge.The convention centre is a focal point of Malaysia’s

new administrative capital. Its seven levels provide a plenary hall for 3000 and two large

conference halls (capital 2000), as well as mini halls, meeting rooms, suites,galleries and

supporting services - yet its footprint occupies only three acres of its 51-acre site, leaving the

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remainder for use as a public park. To achieve this, more than 60 per cent of the spaces are

submerged below ground. The glazed walls of the above ground structure are sloped and

louvered to prevent direct solar gain; the membrane roof is made of Sarnafil. The plenary hall is

renowned for hosting grand and historic events and concerts. Besides hosting the 10th Islamic

Summit, PICC is also a conference venue for high security risk events, hosted by the

government or the private sector. PICC has had many important guests including foreign head

of states and heads of government, important corporate personalities such as the world's

richest man, Bill Gates, as well as the current CEO of Microsoft, Steve Ballmer.

3.3 Architectural Design

Figure 3.3.1 Inspired from Pending Perak (left) to site plan of PICC

The design of the building is based on the shape of the eye of 'pending perak' (a silver Malay

royal belt buckle). However, the structure of the roof was designed similar to a folded origami to

alleviate the plain roundness of the structure. From the frontview, the building's eaves or wings

are lifted at the sides, creating broad overhangings over the raking wall. Most of the walls are

made of glass, so natural sunlight can easily illuminate the auditorium through the raked and

shaded windows.

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Figure 3.3.2 Interior view of Plenary Hall from the stage

Figure 3.3.3 Interior view of Plenary Hall toward the stage

The roof structure, which is geometrically complex, covers the plenary hall and the column-free

banquet hall. The latter space can accommodate 3000 delegates, each with an uninterrupted

view of the stage with the conference and main auditorium floors above supported on a

sculptural system of radial arms.Surrounding these main spaces the ancillary accommodation

follows a conical geometry with the rings increasing in diameter up the building to provide the

larger area needed for the plenary hall itself.

The roof structure is unique with its complicated geometry and long span. The shape of the roof

resembles a ‘pending’ which is a buckle worn in Malay weddings.

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3.4 PICC Master Plans

Figure 3.4.1 Site Plan of PICC

Figure 3.4.2 Front elevation of PICC (North)

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Figure 3.4.3 North South sectional elevation of PICC

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Figure 3.4.4 Floor Plan of Plenary Hall, PICC

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4.0 Sound Source

Figure 4.0.1 Events that carried out in Plenary Hall, and most of them strongly related to

speech

The main activities that carried out in Plenary Hall are talks, convocations, conferences, award

ceremony etc. Most of the events are closely related to speech intelligibility, which are

supposed to giving verbal informations clear so the audience can perceive and understand it.

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4.1 Speech Intelligibility

Speech is composed of phonemes, which are individual and distinctive sounds that, to an

extent, vary from language to language. Normal speech averages between 55 and 65 dBA

sound pressure level at 0.9m to 1.2m from the source.The higher the frequency, the greater a

sound’s directivity, and the less it diffraction. High frequency tones are most easily absorbed

and least diffracted. Speech intelligibility is heavily influenced by two factors, which are power

and clarity.

Power is affected by:

Clarity is affected by:

Distance from speaker Delayed reflections : echoes, near echoes, reverberation

Directional relationship to speaker Duplication of sound source by loudspeakers

Audience absorption of direct sound Ambient noise

Reinforcement by reflectors Intrusive noise

Reinforcement by loudspeakers

Sound shadows

10log3.0)(

VT optimumR

Optimum reverberation time in seconds, for speech.

Whereas

V = Volume of the room (cubic meters) - 52173 cubic meters

)(optimumRT of Plenary hall (52173 cbm) = 1.12 seconds

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A

VTR

16.0

Sabine Formula to calculate reverberation time of PICC, in seconds

Whereas

RT = Reverberation time

V = Volume of the room (cubic meters)

A = total absorption of room area (sqm)

500 Hz

Surface Area Absorption coefficient Abs unit

Wall (fibreboard on

solid backing)

4387 sqm 0.15 658.05

Ceiling (metal 32.5%

perforated ceiling,

backed by 30mm

rockwool)

2637 sqm 0.87 2294.19

Floor (carpet) 2637 sqm 0.50 1318.5

Occupant 3000 0.46 1380

Total Absorption (A) 5650.74

74.5650

)52173(16.0RT

RT = 1.48 seconds

Reverberation time for PICC is 1.48 seconds.

The reverberation time of PICC is took slight longer time than the optimum. It means that the

sound required slight longer time to decay after the sound has been switched off. An increase

of 20% in reverberation time would make the room excessively live and bloom, but it would

affects speech intelligibility.

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4.2 Sound Reinforcement System (Sound Amplifier) To amplify the sound, sound speakers were adapted in order to create higher volume and

power so that audience can listen to every single words clearly. Amplifiers must be rated to

deliver sufficient power to produce intensity level of 80dB for speech.

Listen with the understanding that when the venue fills with people, the reverberation will be

lessened. This natural absorption will help with intelligibility, but it will also absorb high

frequencies disproportionately to low frequencies, which can muddy the sound and affect

intelligibility. In order to obtain the consistency of acoustical experience from one section to

another section, supplement speakers are helpful when distributed in proper manner and

location.

Figure 4.2.1 6 central speakers located high above the stage.

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Figure 4.2.2 Supplemental loudspeaker were installed around the wall of Plenary Hall.

Figure 4.2.3 Central speaker provides wide angle of sound, while 32 supplement speakers are

distributed along the blue axis wall-mounted in the auditorium.

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5.0 Sound Path Ideally, every listener in a theatre should hear the speaker or performer with the same degree

of loudness and clarity. Since this is obviously impossible by direct-path sound, the essential

design task is to devise methods for reinforcing desirable reflections and minimizing and

controlling undesirable ones. Normally only the reflection is considered in ray diagramming

since its strongest.

5.1 Echoes

Figure 5.1.1 Ray diagram of direct (D) and reflected (R1 and R2) sound path in Plenary Hall

(shaded area)

34.0

21 DRRTdelay

Formula of time delay, in milliseconds

Whereas

R1 and R2 - ceiling reflection distance,in meter (R1 = 25m, R2 = 25m)

D - direct distance from speaker to audience, in meter (D = 25m)

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The time delay in PICC is 73.5 msec, is deemed as an echoes because it takes longer delayed

time for speech (maximum 40 msec).

Figure 5.1.2 Ray diagram of direct (D) and reflected (R1 and R2) sound path in Plenary Hall

floor plan. (Red as speaker, Blue as audience)

R1 (47m) + R2 (31m) - D (25m) = 53m

53m is more than 14m, which contributes to the occurrence of echoes in PICC.

When we were there, one of the group mates stood on the stage and clap her hand. We can

hear clearly the same clapping sound after the dying out of the original sound.

However, there are some solutions for echoes. Usually the surfaces that produced echoes are

back wall and ceiling. Ones can:

1. Add panel to lower the ceiling height in order to reflect the sound further back.

2. Add panel at the rear to reduce the back wall height to be exposed.

3. Add absorption to the back wall, to reduce the loudness of the reflected sound.

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5.2 Focusing

Figure 5.2.1 Recessed concave ceiling with voids around to allow light ventilations.

Concave ceiling in PICC Plenary Hall reflected sound into certain areas of the auditorium, so

called sound concentration. This has several disadvantages. It will deprive some listeners of

useful sound reflections and cause hot spots at other audience positions.

Figure 5.2.1 Ray diagrams of how concave ceiling reflects the sound and concentrate into one

specific spot.

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5.3 Room Shape

Figure 5.2.1 Roundness of Plenary Hall tends to encourage the sound to be centralized.

Plenary Hall with circular shape or round walls is undesirable for acoustic system because such

walls concentrate the reflected sound (like spherical mirrors) in particular areas that leads to a

non-uniform sound intensity in the audience area. The sound moves toward the constructive

centre thereby creating echoes. Plenary Hall is well known for form aesthetics but not really an

appropriate for acoustic.

In order to have an adequately low reverberation time, the room was equipped with good

absorption system, so that sound drops off fast rather than highly dispersed within the space.

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Figure 5.2.2 (Before) Sound is played throughout a round room.

Figure 5.2.3 (After) Sounds stopped dispersing in round room with soft,smooth edges.

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6.0 Material used in sound acoustic system Generally, there are four types of materials used in acoustic system, which are:

1. Absorption materials

2. Diffuser materials

3. Reflection materials

4. Noise barrier

Figure 6.0.1 Different behaviour of sound when it contacts on various of materials

1. Sound absorber - absorb acoustical panels and soundproofing materials to eliminate sound

reflections to improve speech intelligibility, reduce standing waves and prevent comb filtering.

Usually the absorption materials are porous materials, like foam fibreglass etc.

2. Sound diffuser - reduce the intensity of sound by scattering it over an expanded area, rather

than eliminating the sound reflections as an absorber would. Temporal diffusers, such as binary

arrays and quadratics, scatter sound in a manner similar to diffraction of light, where the timing

of reflections from an uneven surface of varying depths causes interference which spreads the

sound. It divides the energy of the wave, sending it in many different directions which depletes

its energy faster.

3. Sound reflector - When the sound hits these surfaces it is sometimes reflected back into the

space. These reflections can travel back toward the source or to the receiver as an indirect

sound. Reflections can be used to help distribute and amplify the presentation to all of the

listeners. Of course, this requires specific characteristics and location of reflective surfaces.

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6.1 Wall

Figure 6.1.1 Wall surface of Plenary Hall, PICC

Figure 6.1.2 Circular wall of Plenary Hall, PICC

Wall plays a significant role in sound acoustic system as it wraps the envelop of interior.

Therefore, the chosen materials and construction details should be paid attention.

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6.1.1 Perforated Acoustic Panel

Figure 6.1.1.1 Front view of perforated acoustic panel with its dimension, in mm

Figure 6.1.1.2 Timber perforated acoustic panel is installed on the wall

This timber perforated acoustic panel, with octagon shape, is mainly functioning as sound

absorber and sound diffuser. The edge of the panel can helps to reduce the intensity of sound

by scattering it over an expanding space. The tiny dents on the panels are meant to be

transparent that the sound waves pass through it, without being diminished or reflected, to

encounter the acoustical treatment that lies behind. As a result, it can lower down the

reverberation time of the auditorium, so that low frequency reverberation time able to be

controlled.

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Figure 6.1.1.3 Overall function of sound acoustic elements such as panel, timber plank, fabric

and wall

Advantage of timber perforated acoustic panel:

1. Absorbing and diffusing sound

2. Add privacy and intimacy to the space

3. Improve speech intelligibility, recording quality and listening clarity

4. Aesthetically comfort and locally symbolic in materiality

Figure 6.1.1.4 Construction detail of timber perforated acoustic panel

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Figure 6.1.1.5 Perforated acoustic panel as the backdrop of the stage

Figure 6.1.1.6 Close-up view of the perforated acoustic panel

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6.1.2 Acoustical Fabric

Figure 6.1.2.1 Acoustic fabric (red boxed) covers most of the surface of the wall

The wall of the PICC are fully covered with fabric wrapped acoustic panels for sound

absorption and noise control. The panels are features with fire retardant needs to resist burning

and withstand heat. There are few types of panels that absorb sound, for instance barrier and

absorber panels with a mass vinyl sound barrier septum, high impact panels and tackable

panels. A fabric wrapped acoustic panels can even have custom artwork on the it, which is

normally called artwork acoustic panels.

Figure 6.1.2.2 Permeability of the fabric allows the sound energy to travel through

A fabric's job on an acoustic panel is to not absorb sound itself, but to allow sound-absorbing

products behind the fabric to do their best work. The fabric should never reflect the sound

before it can travel to the absorbing product. All surfaces, fabrics included, reflect sound waves

to some extent.

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6.1.3 Timber Frame

Figure 6.1.3.1 Timber frames that draws across the wall surface

These timber acoustic planks preserve the liveliness of the space because they don’t absorb

much sound energy, instead they disperse it, spreading energy around the room. Usually it is

made out of hardwood due to its high density. The ideal acoustic diffuser with its surface that

causes an incident sound wave from any direction to be evenly scattered in all directions, by its

surface profiles. Such profiles able to break up the sound wave so it travels along many much

smaller paths. The timber acoustical planks can be decorative element as well. In this case, it

mimics the design motifs of Mengkuang weaving patterns.

Figure 6.1.3.2 Stepped profile of acoustic planks, disperse the sound with its irregular or

uneven surface

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Figure 6.1.3.3 Uneven profile on seating divider wall for sound diffusion purpose.

Figure 6.1.3.4 Grooved acoustic planks on translator and VIP room.

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6.1.4 Wall Acoustic Panel

Figure 6.1.4.1 The placement of sound diffuser panels(red boxed) on right wall of Plenary Hall.

There are 2 panels facing to the stage in the hall.

Figure 6.1.4.2 Geometric sound diffuser panels arranged in such stepping configuration to

disperse the sound waves into different directions

Sound diffusers are designed to disperse and scatter sound waves, thereby to reduce standing

waves and echoes to improve sound clarity. A diffuser are normally used in critical listening

environments, for instance recording studios, control rooms, auditorium and music production

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rooms. Sound diffusers doesn’t not trap or eliminate the sound like sound absorbers, it

maintains the ‘live’ ambience by reducing standing waves and slap echo.

Diffusers are manufactured from molded plastic or E-Glass and wrapped or covered in various

fabrics. Sound diffusers are typically used in combination with other materials like sound

absorbers, bass traps, ceiling clouds or other provisions to achieve the desired results for the

applications.

At the same time, it acts as a reflector so that the direct sound can be reflected or disperse to

wider range of audience.

Figure 6.1.4.3 The acoustical panel (red colored) reflects the direct sound from the speaker

(red dotted), to other regions of audience.

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6.1.5 Translator and VIP Room

Figure 6.1.5.1 Translator room(top) and operator room (bottom) cantilevered against the wall

There are 2 rooms built on the both walls of Plenary Hall, PICC, which accommodates

translator and VIP room. From the picture attached above, the room on the upper flor is for VIP

therefore the glass is not treated for sound acoustic for the visual quality. Whereas the lower

floor room is for translator, where they should not be affected by the sound outside the room in

the hall. Factors that affect the acoustical performance of the glass against the sound are:

1. Thickness of glass

Figure 6.1.5.2 Graph of relation between sound frequency and glass thickness

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Thicker glass tends to provide greater sound reduction even though it may actually transmit

more sound at specific frequencies. Every glass pane thickness has a weak frequency value;

that is, a frequency for which that glass is less 'noise absorbent' than for the others. That value

is known as critical frequency. At low frequencies, sound attenuation is directly proportional to

mass.

2. Lamination (treatment of glass)

Figure 6.1.5.3 Graph of relation between sound frequency and laminated / unlaminated glass

A laminated glass will attenuate sound transmission more than a monolithic glass of the same

mass. the critical frequency effect disappears due to the sound damping provided by polyvinyl

butyral (the soft interlayer used to permanently bond the glass panes together dissipates

energy by vibration).

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3. Air cavity effect

Figure 6.1.5.4 Graph of relation between sound frequency and air cavity between glass

a standard double glazed unit does not reduce sound transmission much more than a

monolithic glass. What matters is the thickness of the air space between glass panes, but only

for really wide cavities.What really matters is the width of the air space, not the small one found

at double glazing but the one of a double skin. The ideal cavity width to boost sound

attenuation is 200 mm.

Figure 6.1.5.5 Operator room glass wall was installed with acoustical film (darker)

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6.2 Ceiling

Figure 6.2.1 Concave ceiling that visible from the interior is actually the bottom part of the roof.

By definition perforated panel have perforations on the front panel, that allow for air movement

through them into the cabinet insides. A diaphragmatic absorber has a face panel that does not

have any perforations and is solid. Even if the cabinet fill material is the same, the

diaphragmatic absorber will always go lower than a perforated absorber.

Figure 6.2.2 Construction details of a perforated ceiling panel, composed of :

1. Steel panel with 32.5% perforated

2. 2. 30mm thk rockwool

3. 3. 10mm gypsum board

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Composed of compressed mineral wool or foam, sound absorbing acoustic panels absorb

sound waves to reduce general noise, clarify speech and limit reverberation within enclosed

areas. Using acoustic panels essentially “cleans” an area of unnecessary sound debris that

makes it impossible to hear a person who talking, enjoy beautiful music or record something as

crisply as possible.

When sound waves travel through the air and strike wall- or ceiling-mounted noise reducing

panels, fibreglass fibres or foam pores vibrate, increasing friction among the pores or fibres.

These vibrations quickly reach a point where enough friction is created for the conversion of

sound energy to kinetic (heat) energy, which is simply the energy of an object in motion. Since

kinetic energy can’t be contained, it dissipates quickly, leaving no sound waves and, naturally,

no sound.

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6.3 Floor

Figure 6.3.1 Carpet covers over the floorin Plenary Hall, PICC

While carpets reduce noise transmission through the floor in muiti-storied buildings, the degree

of actual noise reduction, as well as people’s perception of it, are dependent on the frequency

distribution of the sound.Wool carpet because of the fibre’s natural ability to absorb a wider

range of frequencies, also provides superior sound insulation for those below.

Figure 6.3.2 Carpet absorbs the impact or retard the energy of the sound

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Carpet can improve the impact insulation class of common flooring ceiling systems by

approximately 30dB. The porosity of the surface of carpets means that sound waves can

penetrate into the pile, rather than being reflected back into the room as they would from a

smooth surface.

Figure 6.3.3 Absorption of carpet in relation to time and impact

Carpets are extremely effective sound absorbers because the individual fibres, pile tufts and

underlay have different resonant frequencies at which they absorb sound. Wool carpets are

particularly effective, as the millions of wool fibers in an area of carpet have a range of lengths,

diameters, crimps and spirallity, which enables them to absorb sounds over a wide range of

frequencies.

Figure 6.3.4 Construction details of acoustical floor carpet

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6.4 Seating

Figure 6.4.1 3000 seatings provided in Pleanary Hall, PICC

A reflective front stage area provides strong early reflections that are integrated with the direct

sound and enhances it, On the contrary, strong late reflection and reverberations, such as from

rear walls, would not be integrated and may produce echoes.

To accommodate this, the stage area and front of the hall are made reflective and absorption is

placed in the rear of the hall; as well as in the seating area.

Figure 6.4.2 Close-up view of an individual chair

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Figure 6.4.3 10mm holes on the base of the chair

Figure 6.4.4 Fabric with small dents for permeability

Like the remaining of the structure interior, local material and locally manufactured finishes

custom designed for PICC was used for the construction of the seats. Local timber resulted in

the wooden perforated panels along the bottom of all 3000 seats. Having a wide sound

absorption spectrum, allows it to aid the locally weaved carpets below in absorbing and

diffusing sounds. On top of the wooden perforated panels, the seats in PICC consists of fabric

finishes, and moulded timber panel to the back as well as the arms.

Polyurethane foam, a high density foam with a long lasting nature, with its ability to absorb

sound and prevent echo is utilised in the seats.

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In order to improve sight lines and fidelity in the seating area, seats in PICC were arranged on

a sloping floor; allowing the listener to receive more direct sound that would be available on a

flat floor. A sloping (raked) floor is desirable in halls where audience sound absorption must

be minimised.

Figure 6.4.5 Chart shows the effect of both occupied and unoccupied seats in chairs of low

absorption (above) and high absorption (bottom). Source: Choi Y.J.

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6.5 Door

Figure 6.5.1 Exit door

Figure 6.5.2 Entrance door at the lobby

Average transmission loss values for doors, that is the arithmetic average of the octave band

transmission losses in the range of 150Hz to 3000Hz , are not useful for two reasons :

1. The very important low-frequency attenuation data are absent.

2. Sharp peaks and valleys in the curves are unrecognized. As a result, a particularly

troublesome frequency may not be sufficiently attenuated. In the absence of a

completely frequency analysis, the STC rating of a door is a better indication than an

average transmission loss figure.

Louvered doors ( and doors undercut to permit air movement ) are useless as sound barriers.

The most important step in soundproofing doors is complete sealing around the opening. A

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door in the closed position. A door in the closed position should exert pressure on gaskets,

making the joints alright.

When a single door does not provide sufficient attenuation and specially constructed

high-attenuation commercial acoustic doors are not practical, a simple and very effective

technique is the construction of a sound lock consisting of two doors, preferably with sufficient

space between them to permit full door swing. All surfaces in the sound lock should be covered

completely by absorbent material and the floor carpeted. Such an arrangement will increase

attenuation across the board by at least 10dB and by as much as 20dB at some frequencies,

depending upon the shape of the sound lock and the type, amount, and mounting of absorptive

material in the sound lock. The two doors of the sound lock must be gasketed.

Figure 6.5.3 Gasket installation on the door frame so it can seals better as a sound proof door

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Figure 6.5.4 Transom seal at the door bottom, in contact with the carpeted floor, in Plenary Hall,

PICC

Another important consideration with respect to sound intrusion via doors is the location fo a

door relative to sources of unwanted sound. This is particularly important in multiple-resident

buildings of all types, including private homes, apartment houses, hotels, and rooming houses.

The same principle applies to commercial spaces where numerous private spaces such as

offices open onto a common lobby or foyer.

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7.0 Conclusion

Through this assignment, we are able to to identify the sound source and main activities carried

out in PICC which mainly consists of ceremonies and conferences. These leads to in depth

research on the speech intelligibility that shows how the sound from the speaker is delivered

throughout the interior space. Other than that, we are able to deliver the sound paths, echoes

and focusing ( sound concentration ) by using ray diagrams. We are also able to identify the

main materials used in the sound acoustic system for the PICC which consists of the

components – walls, ceiling, floor, and door.

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8.0 References

Book

1. Grondzik W.T., Kwok A.G., Stein B., Reynolds J.S. (2010). Mechanical and Electrical

Equipment For Buildings. John Wiley & Sons.

2. McMullan, R. (2012). Environmental Science in Buildings. McMillan.

Online Resources

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