Upload
dhurai-kesavan
View
231
Download
0
Embed Size (px)
Citation preview
7/29/2019 02 Material
1/37
Material Copyright Prof Schierle 2011 1
St ruc tu re
ma te r i a l
Wood
Steel
Concre te
Masonry
Fabr ic
7/29/2019 02 Material
2/37
Material Copyright Prof Schierle 2011 2
Rupture Length
Rupture length is themaximumlengthabar of
constant cross sectioncanbesuspendedwithoutruptureunder itsweight in tension(compression
for concrete&masonry)
Rapture length defines the efficiency of material asratio strength / weight:
R = F / where
R = rupture lengthF = breaking strength
= specific gravity (self weight)
Thegraph ispartlybasedonastudyof the
Light weight Structures InstituteStuttgart University
7/29/2019 02 Material
3/37
Material Copyright Prof Schierle 2011 3
Energy use
For simple beam of
Aluminum [Aluminium] Concrete [Bton]
Steel [Acier]
Wood [Bois]
demonstrates wood requires
much less energy !
Study of EPFL
(Ecole Polytechnique Federale de Lausanne)
Wood
7/29/2019 02 Material
4/37
Material Copyright Prof Schierle 2011 4
WoodTypes:
Balloon framing (rare) Platform framing
Heavy timber framing
Challenges:
Combustible
Termite attacks
Decays in variable humidity
Limited height and floor area
Advantages:
The only renewable material Warm, natural appearance
Low energy required
Easy to work
Low cost
7/29/2019 02 Material
5/37
Material Copyright Prof Schierle 2011 5
Platform framingPlatformframing is used for low-riseresidential
structures, due toeconomy &flexibility. 2x4studs
@16 reach fromplatformtoplatform. Double
topplates overlapat cornersandsplices. Plywood
sheathing, nailed tostuds, resists lateral windand
seismic loads. Joists, usually2x12@16 support
plywood floor androof (platforms). Blocking
resists joist bucklingandsupportsplywoodpaneledges to transfer shear. Standardplywoodand
gypsumboardpanels48 (4) widematch2, 3, or 4
joist/studspaces of 24, 16 or 12, respectively.
A Joists, 2x12or 2x10@16", 24, or 12 o.c..B Blocking
C Doubletopplates overlapat cornersandsplices
D Studs, 2x4, 2x6, or 3x4@16 or 24 o. c.
E Bottomplates
F Doubleplates supporting joists
G Anchor bolt, 1/2 @4 o. c.
H Soleplate, min. 6" abovesoil
I Concretefoundation
Maximumheight: 3stories (4with firesprinklers)
7/29/2019 02 Material
6/37Material Copyright Prof Schierle 2011 6
Woodframe house
Wall erection
Plywood shear wall resists
lateral wind and seismic loads
7/29/2019 02 Material
7/37Material Copyright Prof Schierle 2011 7
Clifton Condos, Beverly HillsArchitect: Schierle
7/29/2019 02 Material
8/37Material Copyright Prof Schierle 2011 8
Terrace Homes, Hermosa BeachArchitect: Schierle
7/29/2019 02 Material
9/37Material Copyright Prof Schierle 2011 9
Terrace Homes
Hermosa Beach
7/29/2019 02 Material
10/37Material Copyright Prof Schierle 2011 10
Heavy timber framing
7/29/2019 02 Material
11/37Material Copyright Prof Schierle 2011 11
Timber house
Architect: Thomas Herzog
(rods resist lateral load)
Gamble house PasadenaArchitects: Green and Green
7/29/2019 02 Material
12/37Material Copyright Prof Schierle 2011 12
SteelTypes:
Heavy steel
Light gauge steel
Challenges:
Requires much energy to produce
Higher cost than other material
Requires fire proofing
Requires accurate workmanship Limited availability in some countries
Com
pression
Tension
Hysteresis loop
(test stress-strain curve)
E = Energy absorbed byductility
- Strain +
Advantages:
Can be recycled Ductile (absorbs seismic energy)
Lighter than concrete and masonry
(small seismic forces)
No limitation of height or floor area
7/29/2019 02 Material
13/37Material Copyright Prof Schierle 2011 13
Heavy steel shapesProfiles: typical labels
1. W-shape, light (W14x22)
2. W-shape, heavy (W14x730)3. S-shape, Standard (S12x50)
4. W-shape, wide flange (W16x40)
5. C-shape, Channel (C10x30)
6. T-shapeCut from S-shape (ST6x25)
Cut from W-shape (WT8x20)
7. Angle, unequal legs (L6x4x)
Double angle (DL6x4x)8. Angle, equal legs (L4x4x)
Double angle (DL3x3x)
9. Pipe
Standard (P4)Extra strong (XP4)
Double extra strong (DXP4)
10. Structural Tubing
Square (ST6x6x)Rectangular (ST8x4x)
7/29/2019 02 Material
14/37Material Copyright Prof Schierle 2011 14
Floor / roof framing
7/29/2019 02 Material
15/37Material Copyright Prof Schierle 2011 15
Steel joints
1 Pin joint, transfers only beam shear to column
2 Classic moment joint, transfers shear and bending moment3 Dog-bone moment joint, reduces stress for seismic safety
4 Joist to beam joint with top flange cut back
5 Beam to beam joint with both flanges cut back
A Column
B Beam
C Connector angles, welded in shop, bolted in field
D Machine bolts, usually installed in field to connect beam
E Welded connection of beam flanges to column
F Stiffener plates resist bending stress from beam flanges
G Secondary beam / joist supported by primary beam / girder
7/29/2019 02 Material
16/37Material Copyright Prof Schierle 2011 16
Steel moment frames
Beam / column moment jointprovides lateral resistance
7/29/2019 02 Material
17/37Material Copyright Prof Schierle 2011 17
Truss floors
Joist and beam roof
7/29/2019 02 Material
18/37Material Copyright Prof Schierle 2011 18
Expressed steel
Hillside houseArchitect: Helmut Schulitz
Braced frame
Imos factoryArchitect: Richard Rogers
Cable stayed roof
7/29/2019 02 Material
19/37Material Copyright Prof Schierle 2011 19
Light-gauge steel(cold-rolled)
1. Channel stud (2 6)
2. C-stud (2 6)
3. I-stud (3 5/8 8)
4. C-joist (6 12)5. I-joist (6 12)
7/29/2019 02 Material
20/37Material Copyright Prof Schierle 2011 20
Light-gauge steel
7/29/2019 02 Material
21/37Material Copyright Prof Schierle 2011 21
ConcreteTypes:
Site cast
Precast Prestressed
Advantages:
Widely available
Can be recycled Many finishes
Takes any form
Fire resistant
Durable
Challenges:
Heavy weight
(large seismic forces)
Requires rebars
to resist tension Possible cracks
without prestress
7/29/2019 02 Material
22/37
Material Copyright Prof Schierle 2011 22
Concrete properties: strong in compression
weak in tension
steel re-bars resist tension
7/29/2019 02 Material
23/37
Material Copyright Prof Schierle 2011 23
Site cast concretefacilitates free forms but
formwork may be costly
7/29/2019 02 Material
24/37
Material Copyright Prof Schierle 2011 24
Precast Concrete
Challenges:
element joints
transportation cost
Advantages:
repetitive use of formwork
factory quality control
7/29/2019 02 Material
25/37
Material Copyright Prof Schierle 2011 25
Precast Concrete
7/29/2019 02 Material
26/37
Material Copyright Prof Schierle 2011 26
Masonry
Types:
Brick masonry Concrete masonry
Stone masonry
RomanaqueductSegovia,Spain
RomanaqueductPontduGard
France
Advantages:
Widely available
Can be recycled Earthy appearance
Fire rated
Durable
Challenges:
Heavy weight
(large seismic forces) Requires rebars to
resist seismic forces
Limited height
Historicstonemas
onry:
7/29/2019 02 Material
27/37
Material Copyright Prof Schierle 2011 27
Brick Masonry
CMU (Concrete Masonry Units)
7/29/2019 02 Material
28/37
Material Copyright Prof Schierle 2011 28
Modular coordination
Based on unit sizeA Inside dimensions: # of units + 1 joint
B Outside dimensions: # of units 1 joint
C System dimensions: # of units
3 units+4 joints
5 units+4 joints
4 units+4 joints
7/29/2019 02 Material
29/37
Material Copyright Prof Schierle 2011 29
Concrete masonryCMU: Concrete Masonry Units
Minimum reinforcement
Rebars around openings
Insevere seismic areas:
Horizontal & vertical rebars @ 4 feet
Inmoderateseismic areas:
Horizontal rebars @ 10 feet
Vertical rebars @ 4 feet
7/29/2019 02 Material
30/37
Material Copyright Prof Schierle 2011 30
Brick masonry
Minimum reinforcement
Rerbars around openings
Insevere seismic areas:
Horizontal & vertical rebars @ 4 feet
Inmoderateseismic areas:
Horizontal rebars @ 10 feet
Vertical rebars @ 4 feet
7/29/2019 02 Material
31/37
Material Copyright Prof Schierle 2011 31
CMU wall with rebars Grouting(bonds rebars with masonry)
7/29/2019 02 Material
32/37
Material Copyright Prof Schierle 2011 32
San
DiegoCon
ventionCe
nter(anticlastic)
Architect:ArthurE
rickson;Engineer:HorstB
erger
Advantages: Light-weight
(less seismic load)
Translucent
(daylight saves energy)
Fabric
Types:
Anticlastic (saddle shape) Air supported
Air inflated
Challenges:
Fire rating
(Teflon coated fiber glass isfire rated; polyester is not)
Durability (about 30 years)
7/29/2019 02 Material
33/37
Material Copyright Prof Schierle 2011 33
Air supported
Inside air pressure
greater than outside
Require revolving doors
to keep air pressure
Air inflated
Air pressure betweendouble membrane or tubes
7/29/2019 02 Material
34/37
Material Copyright Prof Schierle 2011 34
Anticlastic Membranes
Stadium roof Oldenburg, Germany
Engineer: Schlaich / Bergermann
7/29/2019 02 Material
35/37
Material Copyright Prof Schierle 2011 35
Stadium roofs
Engineer: Schlaich / Bergermann
Stuttgart
Kuala Lumpur
7/29/2019 02 Material
36/37
Material Copyright Prof Schierle 2011 36
Sw
issExpo64
Se
aWorldVallejo
Architect:Schierle
Engineer:ASI
Architect:Saugey/Schierle
Engineer:Froadveaux/W
eber
7/29/2019 02 Material
37/37
St ruc tu re
ma te r i a l
Wood
Steel
Concre te
Masonry
Fabr icse in t r ins ic beau t y