Building Scienceⅱ Bld61303 Project1
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BUILDING SCIENCEⅡ BLD61303 PROJECT1 A CASE STUDY ON ACOUSTIC DESIGN TUTOR: AR.EDWIN CHAN AKIF ZOLKEPLEE 322927 ANDIKA SETIABUDI 326483 DEENIE H’YATT 319719 ISYRAQ NASIR 322177 JIJI NG 0904Y72861 MOHD HAFIZ BIN MASRI ONN 334944 MUHAMMAD AQIL AZLI 326479 NATASYA JASMIN TAMSIR 324222 WATANABE KOHEI 332172 TABLE OF CONTENTS 1.INTRODUCTION P2 1.1 AIM & OBJECTIVES 1.2 SITE INFORMATION 1.3 DRAWINGS 2.ACOUSTIC THEORY P3 2.1 ACOUSTICS IN ARCHITECTURE 2.2 SOUND INTENSITY LEVEL 2.3 REVERBERATION, ATTENUATION, ECHOES AND SHADOW 2.4 ACOUSTIC DESIGN FOR AUDITORIUMS 3.METHODOLOGY P10 3.1 EQUIPMENT 3.2 DATA COLLECTION METHOD 4.ACOUSTIC ANALYSIS P13 4.1 AUDITORIUM DESIGN 4.2 MATERIALS 4.3 ACOUSTIC TREATMENTS & COMPONENTS 4.4 SOUND & NOISE SOURCES 4.5 SOUND PROPAGATIONS AND RELATED PHENOMENA 5.OBSERVATION, DISCUSSION & CONCLUSION P16 6.REFERENCES P23 1 1.0 INTRODUCTION 1.1 AIMS & OBJECTIVES “The aim of this project is expose and introduce students on the actually auditorium design layout that can influence the effectiveness of the public address(PA) system in a particular hall.” ーfroM Module Outline. The objectives of the report are as follows ; 1. To conduct an in-depth exploration of the auditoriuM typology based on its layout, designed with an intention for a specific acoustic perforMance according to the needs of its functions. 2. To develop a robust understanding of the physics behind the acoustic quality of an auditoriuM. 3. To analyse the relationship between acoustics and the Materials, spatial planning and context of an auditoriuM. 12 1.2 SITE INFORMATION 1.2.1 BASIC INFORMATION Name of AuditoriuM : Damansara Utama Methodist Church (DUMC) Location : Seksyen13, 46200 Petaling Jaya, Selangor, Malaysia Type of Construction :Multi-purpose auditoriuM Year of CoMpletion :2005 Total VoluMe :15675m2 Total Seat :2301 seats 1.2.2 HISTORICAL BACKGROUND Damansara Utama Methodist church (DUMC) was started in 1980 by a group of 22 professionals and 3 children froM SSMS (Sungai Way-Subang Methodist Church). They started of in a shop lot preMise in Damansara Uptown before Moving to a factory lot in Taman Mayang in 1993 to accoMModate the fast growing congregation which at this point had reached 500 people. The Chinese congregation was started in 1996 as the first vernacular service in DUMC. At the same tiMe, to accoMModate the growing size of the congregation, More services were held each weekend. By 1998, they were having three celebrations weekly at this point had reached 500 people. The nuMbers continue to grow until 2007 when they Moved to the current preMise - Dream Centre. At present tiMe, the congregation stands at 4500 worshippers weekly across seven different vernacular services. 3 1.3 DRAWINGS GROUND FLOOR PLAN FIRST FLOOR PLAN 4 2.0 ACOUSTIC THEORY 2.1 ACOUSTICS IN ARCHITECTURE Architectural acoustics is the science of planning and building a structure to MaxiMise sound flow and reMain effective at extreMe capacities. To reMain audible coMfort in a building or space, architectural acoustics play a huge role. Certain Measure of sound intensity can be categorized as coMfort levels for the users are applied here. The architectural acoustics are affected by a few factors such as the buildin envelope design froM exterior to interior or vise versa and nature of Material used in the interior design as well as inter-space noise control. Sound source will be identified before the application of architectural acoustics in a building. 2.2 SOUND INTENSITY LEVEL Sound intensity is defined as the sound power per unit area (watts/m2) I(db)=10log [I/I ] Intensity in decibels 10 0 2.3 REVERBERATION, ATTENUATION, ECHOES AND SOUND SHADOWS REVERBERATION ; In closed interiors of More or less substantial size, the listener does not only hear a direct sound but a series of its delayed repetitions, that bounce off the confining surfaces. Because the energy of sound waves is absorbed at every bounce during their travels, these repetitions becoMe weaker over tiMe. When the source of sound is turned off, the amount of reflected energy in the rooM decreases until it is entirely absorbed. This gradual dying-out of sound is called reverberation. RT60=0.161Vm/Sa RT60=Reverb time in seconds Vm=Volume in cubic meters Vf=Volume in cubic feat Sa=Total absorption, sabins. 5 ATTENUATION ; Nature/Energy level of sound as it propagated through MediuMs of different density and scatters to the surrounding environMent. α=Energy Absorbed / Incident Energy ECHOES ; Sound reflection is as ubiquitous as the cosMic radiation that surroundings us always. Echoes are defined as sound reflections that is required to the listener with a perceptible Magnitude. Multiple echoes create Reverberations. D=VT SOUND SHADOWS ; Areas that are shielded froM sound waves through MediuMs that either absorb or reflect such waves to a considerable degree. 2.4 ACOUSTIC DESIGN FOR AUDITORIUMS Goals ; 1.Preservation of sound intensity (longer the better) 2.Clarity in sound delivery 3.OptiMuM reverberation tiMe 4.Prevent excessive vibrations 5.Reasonably reduce external noise 6 3.0 METHODOLOGY 3.1 EQUIPMENT LIST Digital Sound Level Meter Digital Camera Measuring Tape / Laser Distance Measurer Bluetooth speaker Tone generator (iPhone app) HuMan Specifications of the speaker ; -Bluetooth transMission distance: 10M -Bluetooth version: 3.0 ClassⅡ, Support A2DP V1.2, AVRCP V1.4 profiles -Stage height: 1.4M Specifications of the tone generator ; -Frequency range: 0hz-20000hz -Tested frequency: 125hz, 500hz, 2000hz 7 3.2 DATA COLLECTION METHOD MEASURING DIMENSIONS -Accessible areas : Long Measuring roll tape (up to 9M) -Ceiling height : Laser distance Measure 0 1 5 10 15 20 MEASURING SOUND INTENSITY LEVEL 1. Set bluetooth speaker at the centre of the stage at 1.6M height froM floor. 2. Take a controlled sound level at 1M away froM sound source at 125hz, 500hz and 2000hz. 3. Take a sample at 5M away froM sound source at 125hz, 500hz and 2000hz. 4. Repeat sample taking at Multiples of 5M. 8 4.0 ACOUSTIC ANALYSIS 4.1 AUDITORIUM DESIGN 4.1.1 SHAPE OF AUDITORIUM The shape of an auditoriuM affects the way sound travel froM the speaker to the audience. The AuditoriuM is boxed within a structure in a fan shaped arrangeMent. The arrangeMent of the seats in this Manner allows the audience to focus at a same point in the auditoriuM giving the iMpact of intiMacy not just between the audience and the stage, but also to each other. CoMparing to a horizontal seat distribution, this arrangeMent allow audience to face forward without having to shift sideways or turn their heads to a certain angle to watch the perforMance. Other than effective and good seats arrangeMent, the angle of the auditoriuM is very iMportant in delivering the sound froM the speaker to the audience. The MaxiMuM angle for optiMuM listening condition is 140o for a wide fan arrangeMent and the angle of the auditoriuM is at 150o which exceeds the liMit. Audience situated beyond the suggested liMit are going to experience a poor listening condition. However, the seats beyond the angle liMit is reserved for parents with strollers. By having that, parents with babies are not going to be affect Much by the loud noise coMing froM the speaker. The figure is showing the limit region within 140o having a good sound quality and the red region showing seats experiencing low quality of sound. 9 4.1.2 CEILING DESIGN AuditoriuM ceiling is different froM any other types of rooM as the ceiling should not be parallel to the floor. This is to avoid any potential flutter echo that are going to disrupt the sound quality inside the auditoriuM. AuditoriuM ceiling geoMetry is designed to direct sound reflection towards the seating area as the voluMe increased along the way. Even though AuditoriuM ceiling is not like any other rooM, soMe design should be avoided such as doMes, cylindrical arches and barreled ceilings due to the creation of sound foci. As for Damansara Utama Methodist Church, the concave design of the ceiling panels helps to direct sound collected froM the speaker to all the audience. The ceiling panels function is to distribute sound to the whole auditoriuM. It helps to propagate sound even without the help of sound speakers. Figure above is showing the reflection of sound waves by the ceiling towards the audience. 10 4.1.3 LEVELING OF SEATS With the shape of the rooM and the design of the ceiling, it still does not coMplete the coMMitment on how a good sound quality is going to be produced. The levelling of seating area in the auditoriuM is very iMportant as it will affect the sound collect by the audience based on the place that they are sitting. There is a total of about 2200 seats in the auditoriuM arranged in a fan shaped Manner to achieve uniforM sound quality. The iMportance of levelling of the seating is to ensure all the audience receive alMost the same sound quality as the sound travel to the rear of the rooM. Despite of having More than 2000 seats, they are arranged in groups and placed at different 3 different level. Figure above shows the whole view of the arrangement of seats 11 4.1.4 GROUND FLOOR PIT At this level, the sound distributed to this seating is not uniforM because of the placeMent of seats on the same level. The sound intensity decreased as the seat goes deeper to the far back of the auditoriuM. The arrangement of seats at the Ground Floor Pit 4.1.5 GROUND TERRACE The ground terrace seating level is just behind the ground floor pit. It is elevated froM the ground floor pit but are not evenly place.