ACOUSTICAL ANALYSIS of the ACADEMIC BUILDING

Transcription

1 On the ACOUSTICAL ANALYSIS of the ACADEMIC BUILDING (Next to FUTA Geotechnical Laboratory) FEDERAL UNIVERSITY OF TECHNOLOGY AKURE. AKURE, ONDO STATE. Compiled By ARC/08/ OLAYINKA, Temitayo Ayodeji. ARC/08/ KASSIM, Jemil Olamilekan. Submitted to: Course Co-ordinator Prof. Olu Ola Ogunsote. JULY

2 TABLE OF CONTENTS Cover page - 1 Table of Contents Abstract - 4 CHAPTER ONE Brief knowledge of Acoustics in Architecture 1.0 Introduction Definition of Terms Aim and Objectives Reasons for the Study of Acoustics in Buildings - 6 CHAPTER TWO General Overview of Study Building ACADEMIC BUILDING, F.U.T.A, Akure, Ondo State. 2.0 Building Description Location Architectural Design Finishing Materials Walls Ceilings Floor Fenestrations (door & windows) 2.4 Illustrations of Noise Sources External and Internal External and Internal Pictures of Study Building - 11 CHAPTER THREE Analysis of general Acoustics of Study Building. 3.1 Analysis of Noise Sources Internal Noise

3 3.1.2 External Noise CHAPTER FOUR Methods of Improving General Acoustics of the Study Building 4.0 Proposal for Reduction of Internal Noise Use of Absorbent Screens and Surfaces Installation of Carpet on the Floor Use of a Sound Reinforcement System Full upholstery of seats 4.1 Proposal for Reduction of External Noise Screening of Hall Insulation of Walls Use of Closable Doors and enforcement of closure. CHAPTER FIVE Conclusion 5.0 Conclusion - 15 References 3

4 ABSTRACT This write-up describes the Acoustical Analysis and properties of the ACADEMIC BUILDING (next to FUTA Geotechnical Laboratory), Federal University of Technology, Akure, Ondo State, it does so in terms of its finishes and construction / Building materials, furniture type, arrangements, as well as the sources of noise (both internal and external),so as to give an Indepth analysis of the above mentioned properties of the Study Building. More so, this write up is expected to propose ways of improving the acoustic properties of the Spaces in the Study Building with respect to the outcome of the analysis carried out in other to create a noise free zone and an acoustic friendly environment for the users. Keywords: Acoustics, Noise, Room Acoustics, Sound 4

5 1.0 INTRODUCTION CHAPTER ONE Brief knowledge of Acoustics in Architecture In the evaluation of a building in relation to the environment in the past the past decades, the importance of providing good acoustics has become a predominating issue in the search for a model architectural environment. The issue of noise, its sources and methods of control has been subjected to intense study. Noise control is fundamentally important to the success of any building especially those meant for listening. Therefore a good acoustic environment requires a variety of noise forecasts at an early stage. It determines the difference between excellent sound and the commonly found mediocrity. In recent times it has become imperative for acoustic planning to be incorporated into every design, without this designed spaces and the even the whole physical environment will be subjected to disturbing levels of noise. Acoustic excellence in a learning environment /lecture theatre could be obtained by attaining very low levels of background noise, which may go unnoticed by most people, but diminishes their experience, reducing clarity of sound. Studies have shown that a reduction in background noise and the quality/nature of the absorbing material use significantly reduces audience noise and eliminates the need for amplification of sound. When a lecture theatre is truly quiet, the speaker can use his entire dynamic range and still be heard from every part of the building. In order to be able to deal with the problems of noise in the Small Lecture Theatre, it would be paramount to carry out an analysis of the nature, causes and effects of the noise. These findings coupled with the knowledge of basic acoustics (the nature of sound and its physical properties.) will be of significant importance in solving the noise related problems in the hall hence providing a more conducive learning environment for the users. 1.1 DEFINITION OF TERMS (i) Acoustics: - This simply the science of sound, which involves mainly the study of the room acoustics and the control of noise. (ii) Room Acoustics:- This concerned with the nature, properties and characteristics of sound in an enclosed space. (iii) Noise:- This simply an unwanted or damaging sound that interferes with what people are trying to do or sound, which has an adverse effect on health or safety 5

6 1.2 AIM AND OBJECTIVES The aim of this Acoustic Analysis on the study building is to give various causes of Acoustic disturbances in a lecture or learning environment, giving reference to the types and sources of Noise to the study building. This analysis of Academic Building located Next to FUTA geotechnical laboratory also gives possible ways and recommendation of solving this problem. 1.2 REASONS FOR THE STUDY OF ACOUSTICS The study of acoustics in relation to buildings is necessary to incorporate the knowledge gained into the early stages of design in other to achieve the following: (i) (ii) (iii) To create an acoustic friendly environment for all users including hearing impaired individual. To ensure maximum correspondence between individuals in an enclosed space without disturbance form internal or external source of unwanted sound or noise. To reduce to barest minimum the physiological and psychological effects of noise on humans in the designed space. CHAPTER TWO General Overview of Study Building ACADEMIC BUILDING (next to FUTA Geotechnical Laboratory) F.U.T.A Akure, Ondo State. 2.0 BUILDING DESCRIPTION The Academic Building is two storey Building with 3 floors, designed for use as lecture Classrooms and laboratories for students, including offices for University s Staffs also of the Federal University of Technology, Akure, Ondo State. 2.1 LOCATION The Academic Building is located at the Obanla zone of the University campus; enveloped and surrounded by different school buildings on some sides. Bounded in the North by Nothing but Vegetation and Road Leading to the University Staff Quarters and school Farm, in the South by the Kure Geotechnical laboratory and The School of Science (S.O.S) Building, by the New Security Building on the West end and by Metallurgical and Material(M.M.E) Foundry Workshop and The mechanical Engineering(M.E.E) Laboratory building on the East. 6

7 2.2 ARCHITECTURAL DESIGN The Academic Building is designed as a 2 STOREY Building; it functions presently as a Building that houses lecture classrooms and Laboratory for majorly students of S.O.S students and Offices to Staffs of the University. The building is designed in a rectangular form with a courtyard centralized in the middle with surrounding lobbies linking each wings of the building. The building consist of 12 Lecture Class rooms and 8 Laboratories and close to 40 offices on the last floor of the building The Building is accessible from all 2 sides, its main entrance located at the Southern part and second entrance while id rarely used located on the Northern part. The roof is in form of a hip roof running through a rectangular shape in which a courtyard is embedded and also with the stair halls decked and used for water tank Base. 2.3 FINISHING MATERIALS. The construction materials used for the various components are as follows Walls Two types of walls were used the first was wall of plastered sandcrete hollow block with a texcote paint finish and partition wall made of aluminium panels and glass majorly used in the offices. Wall textured with paint Partition walls used for Offices Ceilings Due to the nature of the Building being a two storey Building, the Ground floor and were decked meaning the concrete slab separating each floors was the ceiling. While the ceiling used on the Last floor was the PVC ceiling Boards. Decking used as ceiling 7 PVC ceiling board used on the last floor

8 2.3.3 Floor The floor finish of the Entire Study Building was made of Ceramic Floor tiles with size being 450 x 450mm 450 x 450mm ceramic floor tiles Fenestrations The main entrance doors at the Southern section is made of glass, the two side doors are made of Aluminium while the Other Entrance on the Northern side is made of Hollow steel burglary door. Other doors in the building such as Toilet doors, store doors, Lecture Class room doors and Offices are made of laminated panelled timber doors. Aluminium Glass door Laminated door Steel entrance door Window openings are made of Aluminium Glass Sliding windows with Hollow steel rectangular Burglary and glass blocks were used in stairhalls Aluminium sliding glass window in classroom Glass blocks used in stair halls 8

9 ILLUSTRATION SHOWING THE SOURCES OF EXTERNAL NOISE ILLUSTRATION SHOWING THE SOURCES OF INTERNAL NOISE 9

10 10

11 EXTERIOR PICTURES OF STUDY BUILDING (ACADEMIC BUILDING FUTA) Front view Right side view Left side view Rear view Car park of Study building View of adjoining buildings INTERIOR PICTURES OF STUDY BUILDING (ACADEMIC BUILDING FUTA) View of a lecture room Setting View of a Lobby View of the Courtyard Office Area of the Building Classroom view of Furnitures 11 View showing one wing of Building

12 CHAPTER THREE Acoustic disturbances (Noise) and Study Building 3.0 ANALYSIS OF NOISE SOURCES The sources of noise have been identified and divide under two major divisions which are Internal Noise Most internal noise is generated through human activities, which include: i. Occasional dragging of furniture on the hard Floor Finish ii. iii. iii. iv. Noise from occasional opening closing of fenestrations. Verbal discussions in the classroom. Movement of students in and out of Lecture class rooms/ Laboratories and movement of staffs in and out their offices Noise from Mechanical devices such as Ceiling fans and Air conditioners Air conditioners along lobby Ceiling fans Dragging of furniture External Noise The major constituents of external noise are: i. Background noise from human (students) conversation and activities as they loiter on the walkways and surroundings of the building. ii. ii. iii. iv. Mechanical Noises from the devices used in the M.E.E Laboratory and M.M.E foundry Workshop Vehicular Noise from activities that cause engine noise, movement of the vehicles and hooting of horns from adjacent car park around the Building. Occasional noise from movement of trees during strong wind. Noise from climatic feature such as noise caused by rainfall, wind noise. 12

13 v. Other occasional external sources of noise such as unprecedented noise from student in political campaign, riots and awareness Vii vii. Noise from air conditioners and pumping machine situated outside the study building Noise from being generated from cars moving along the road leading to staff quarters and School of Management Technology. Noise from Car park Noise from Foundry Workshop Noise from MEE Laboratory Noise From road beside Building Noise along the Walkway Pumping Machine CHAPTER FOUR Methods of Improving General Acoustics of the Study Building The approaches in improving the acoustical aura of the Academic Building would be discussed in relation to the two categories of noise sources in an effort to reduce both external and internal noise to tolerable or barest minimum levels. 4.0 PROPOSAL FOR REDUCTION OF INTERNAL NOISE Use of Absorbent Screens and Surfaces Absorbent materials and surfaces are efficient in reducing noise ensuing from verbal discussions by students as well as any other internally generated noise that would have been aggravated by multiple reflections from walls. The following are effective types of absorbent materials; (i) (ii) Porous absorbents (best for high frequencies) Membrane absorbents (best for low frequencies) 13

14 (iii) (iv) Resonant absorbers (resonators) Perforated panel absorbents. The ceiling boards are acoustic ceiling tiles, which are good sound absorbing materials. Additional sound absorbing panels can be introduced in a narrow band along the upper side of the walls. The use of gypsum board ceiling below floor slabs will allow beneficial reflection from the ceiling to increase the apparent loudness of sounds for the students towards the rear of Classrooms Installation of Carpet on the Floor It is an established fact that noise from impacts such as shifting furniture and footsteps are less in carpeted rooms as compared to rooms with hard floor finish. Carpets however raise questions on indoor air quality and high maintenance costs which must be balanced with acoustical benefits Use of a Sound System This consists of a wireless microphone used by the teacher to pick up his voice, the voice is then amplified and played through a loudspeakers carefully located in the hall to increase the loudness of the speech sounds for the students in the class room, this prevents the lecturer from shouting in order to make him or her audible Full upholstery of seats Use of foam padded and leather finished chairs will go a long way in absorption of some sound as against the effect of reflection which will be felt in the current case of the wooden furniture. 4.1 PROPOSAL FOR REDUCTION OF EXTERNAL NOISE Screening of Building The noise coming from the surrounding walkways and car park can be screened-off using a fence, constructed to enclose the hall especially from the car park Insulation of Walls The walls of the hall could be insulated with absorbent materials embedded within the block wall; the resulting insulated double skin wall offers a greater insulation from both traffic noise and pedestrian noise from walkways Use of Closable doors and enforcement of closure All doors should be changed to a double glazed aluminium framed door provided with door closers and it must be ensured that they are closed after each entry or exit to disallow noise infiltration. The use of artificial air-conditioning system might also help, in order to be able to close all doors and windows to ensure that sound propagation (reflection) is kept within the classrooms / laboratories and offices this also reduces the amount of external noise into the Building. 14

15 CHAPTER FIVE Conclusion 5.0 CONCLUSION The basic acoustic considerations should be made and included in the design of the building before it is constructed to avoid the problem of adjustments to standing structures and cost implications. Acoustic is a very important aspect to be considered in architectural designs most especially in the design academic buildings. Noise control should be of prime consideration in any academic environment; learning requires a serene environment to aid concentration. Apart from the spatial requirements, other factors such as construction materials, site selection, and design and amplification systems for large halls are equally important. An audiologist and acoustical consultant should be included in the design of learning facilities to aid a satisfactory learning environment. REFERENCES R.M.E Diamant; Thermal and Acoustic Insulation Professor Olu Ola Ogunsote (2014); Acoustics and Noise Control Lecture notes Architecture 500level 2006/2007, (April 2007).; Acoustical Analysis on Small LT (Futa) M. Mehta, J. Johnson, J. Rocafort, Architectural Acoustics: Principles and Design