Architecture Technologhy
Technology 03 is about the design of healthy, comfortable and delightful indoor environments. We will explore the forces that influence human health, comfort and delight in the built environment - and influence architectural form.
Internal Loads: people, lights and equipment
Sound: room acoustics and noise isolation
Systems: mechanical systems for heating, cooling, lighting, power, communication, plumbing, fire protection, and conveyance.
ARCH 3200/8250 Large, internal-load dominated buildings whose thermal conditions are dominated by
INTERIOR FORCES:
Daylighting/ Electric Lighting Maximize Visual Comfort - Reduce Energy Use
Mechanical Systems for Buildings Maximize Thermal Comfort – Reduce Energy Use
Architectural Acoustics Acoustical Comfort
Water & Waste Systems Reduce Natural Resource Use
Course Subjects and Objectives
ARCH 3200 Technology 03
3
Week
Topics Readings (MEEB)
Workshop /Quiz
1 F 9/7 2
W 9/12 Architectural Acoustics: Measuring Sound 22.1-22.7 TH Quiz Due
F 9/14 Sound Absorption, Room Acoustics 23.1-23.18
3
W 9/19 Sound Isolation and Noise Control
Workshop
F 9/21 Auditorium Acoustics 24.1-24.36 Quiz 4 W 9/26 Water and Waste Systems 18.1-18.8 TH Quiz Due
F 9/28
5
W 10/3 Water Sources and Municipal Waste 19.1-19.12 Workshop
F 10/5 6
W 10/10 Water and Waste Systems in Buildings 20.1-20.11
F 10/12
Quiz
7
W 10/17 Introduction to Mechanical Systems 12.1-12.14 TH Quiz Due
F 10/19 for Large Buildings 8
W 10/24 Architectural Form and HVAC Systems 12.15-12.21 Workshop
F 10/26
Quiz 9
W 10/31 Architectural Lighting: 13.1-13.28 TH Quiz Due
F 11/2 Vision, Color and Perception 10
W 11/7 Characteristics of Electric Lights 14.1-14.20 Workshop
F 11/9 Bulbs, Lamps and Luminaires, Electric
11
W 11/14 Lighting Design: Prediction Techniques 15.1-15.17 Workshop
F 11/16
12
W 11/21 Lighting Design Strategies and Controls 16.1- 16.32
F 11/23
13
W 11/28 Daylighting Design: Prediction Techniques 17.1-17.30
F 11/30
Case Studies of Integrated Systems
13
W 12/5 Quiz Finals
ARCHITECTURAL ACOUSTICS
1. Basics of Sound and Hearing
• Sound and Perception
• Measurement of Sound
2. Noise: Sounds we don’t want to hear
• Sound Isolation
• Sound Absorption and Noise Criteria
3. Music and Vocals: Sounds we do want to hear
• Room Acoustics
• Performance and Concert Halls
1. SOUND AND VIBRATION
Is sound a particle or a wave?
Sound is a vibration in an elastic medium such as air, water, most building materials and the earth.
Pressure is a force per unit area.
Sound energy progresses rapidly, producing extremely small changes in atmospheric pressure and can travel great distances.
However, each vibrating particle moves only an infinitesimal amount to either side of its normal position.
Pure Tones
A pure tone is a vibration produced at a single frequency.
Complex Sounds
Tp = 1 / f
Tp = period (sec/cycle)
f = frequency (cycles/sec) or Hz (Hertz)
2. WAVELENGTH
l = 1130 / f
l = wavelength (ft)
f = frequency (hz)
3. VELOCITY OF SOUND
Sound travels at a velocity that depends primarily on the elasticity and density of the medium.
Air: 1130 ft/sec
Steel: 16,000 ft/sec
Concrete: 12,000 ft/sec
4. FREQUENCY OF SOUND
Octave bands are identified by their center frequencies. A doubling of the frequency is perceived as the same note or tone, one octave higher.
5. FREQUENCY RANGES OF AUDIBLE SOUNDS
Hearing range for a healthy young person:
20 to 20,000 Hz
Human speech contains energy from about:
125 to 8000 Hz
6. SENSITIVITY OF HUMAN HEARING
7. SOUND INTENSITY AND THE INVERSE SQUARE LAW
I = W/4pd2
I = sound intensity (W/m2) W = sound power (W) d = distance from sound source (m)
I1 / I2 = (d2 / d1) 2
I = sound intensity (W/m2) d = distance from sound source (ft or m)
L1 = 10 log (I / IO)
L1 = sound intensity level (dB) I = sound intensity IO = reference sound intensity,
10-12 (W/m2)
8. DECIBEL SCALE
Change in
Sound Level (dB)
1
3
6
10
20
Change in
Apparent Loudness
Imperceptible (except for tones)
Just barely perceptible
Clearly noticeable
About twice (or half) as loud
About 4 times (or one-fourth) as loud
CHANGES IN SOUND LEVEL
Common Sounds in Decibels
The purpose of the phon scale is to compensate for the effect of frequency on the perceived loudness of tones. By definition, 1 phon is equal to 1 dBSPL at a frequency of 1 kHz
Doubling the distance:
• 6 dB for point sources
• 3 dB for line sources
9. NOISE REDUCTION WITH DISTANCE
Doubling the Distance
From 10 to 80 feet away is three doubling of distance
Three doublings x 6dB / doubling = 18 dB reduction
When Two dB
Values Differ by
0 or 1
2 or 3
4 to 8
9 or more
Add the Following dB
To the Higher Value
3
2
1
0
DECIBEL ADDITION
SOUND LEVEL METERS
PERCEPTION AND LOUDNESS
SOUND LEVEL METERS
Weighting Scales
dBA Closest to human hearing Corresponds to an inverted 40- phon contour and discriminates against low frequencies as does the human ear.
dBC Nearly “flat” Corresponds to an inverted
100-phon contour and does not discriminate against low frequencies. Use this weighting scale to investigate the content of lower frequencies in a sound spectra.
SOUND SPECTRA FOR COMMON SOUNDS