Post on 07-Aug-2020
Timber
Wood as a materialHardwood vs. Softwood
Pith, Heartwood, Sapwood:
Density and moisture content
Anisotropic strength
Moisture Content vs. Relative Humidity
Relative Humidity Moisture Content
0 0
25 5
50 9
75 14
99 23-30
Tangential section Radial section
Horizontal section
Growth ring
Pith
Ray
Outerbark
Innerbark
Cambium
Bark
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Timber
Wood-based productsLayered products Glued laminated timber (glulam)
Plywood
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Inside face
Lamination thickness
Inside faceb
h
12
≤ 3.5mm 1.5 to 1.6 a
=2/5x bb
2a
b
a
a
<=
Image by MIT OCW.
Timber
Wood-based productsLayered products Glued laminated timber (glulam)
Plywood
Particleboards Chipboard
Flakeboard
Oriented Strand Board (OSB)
Timber
Wood-based productsLayered products Glued laminated timber (glulam)
Plywood
Particleboards Chipboard
Flakeboard
Oriented Strand Board (OSB)
Fibreboards Wet method
Dry method (Medium Density Fibreboard or MDF)
Timber
Wood-based productsLow-quality wood
Isotropic & strong
Free dimensions & openings
Panel construction & "black boxes"
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Timber
Timber construction systemsTimber frame construction
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Timber
Timber construction systemsTimber frame construction
Balloon frame construction (timber stud construction)
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Timber
Timber construction systemsTimber frame construction
Balloon frame construction (timber stud construction)
Platform frame construction
Image by MIT OCW.
Timber
Timber construction systemsTimber frame construction
Balloon frame construction (timber stud construction)
Platform frame construction
Panel construction
Image by MIT OCW.
Timber
Timber construction systemsTimber frame construction
Balloon frame construction (timber stud construction)
Platform frame construction
Panel construction
Bearth-Candinas House by Bearth+Deplazes, 1998
Photographs and floor plans removed due to copyright restrictions.
Timber
Timber construction systemsTimber frame construction
Balloon frame construction (timber stud construction)
Platform frame construction
Panel construction
Log construction
Image by MIT OCW.
Timber
Timber construction systemsTimber frame construction
Balloon frame construction (timber stud construction)
Platform frame construction
Panel construction
Log construction
Frame construction
Image by MIT OCW.
Timber
Timber construction systemsTimber frame construction
Balloon frame construction (timber stud construction)
Platform frame construction
Panel construction
Log construction
Frame constructionElement
(loadbearing)RafterPurlin, beamSolid-web beamLattice beam
Span 1(m)
Span1(m)
- 8 m4 - 12 m6 - 16 m8 - 20 m
1/18 - 1/301/15 - 1/241/12 - 1/181/18 - 1/15
h*/l0 1 2 3 4 5 6 7 8 9 10 11 1213 1415 16 1819 202122 2324 2517
Depth of beamh (m)
1/10
1/12
1/15
1/18
1/24
1/30
2.001.901.801.701.601.501.401.301.201.101.000.900.800.700.600.500.400.300.200.100.00
*A beam cross-section (h/b = 2/1) can be used for the initial, rough sizing; Glulam beams are often more slender.
Image by MIT OCW.
Timber
Main reference for lecture contents:“Constructing Architecture” by Deplazes: pp. 77-112
Additional readings relevant to lecture topics:"Fundamentals of Building Construction" by Allen:
&
"Building Construction Illustrated" by Ching & Adams:
chapters on timber and wood construction