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S2017abnMembrane, Nets & Shells 1
Lecture 13
Applied Architectural Structures
ARCH 631
thirteen
membrane, net &
shell structures
lecture
Denver Airport – Birdair.com
APPLIED ACHITECTURAL STRUCTURES:
STRUCTURAL ANALYSIS AND SYSTEMS
ARCH 631
DR. ANNE NICHOLS
SPRING 2017
S2017abnMembrane, Nets & Shells 2
Lecture 13
Applied Architectural Structures
ARCH 631
Membrane and Net Structures
• form follows
pressure or
tension
S2017abnMembrane, Nets & Shells 3
Lecture 13
Applied Architectural Structures
ARCH 631
Membrane and Net Structures
• types
– fabric
– cables
– pneumatic
– inflated
http://nisee.berkeley.edu/godden
S2017abnMembrane, Nets & Shells 4
Lecture 13
Applied Architectural Structures
ARCH 631
Membrane and Net Structures
• sensitive to aerodynamic effects of wind
– fluttering
• stabilization
– rigid supporting framework
– prestressing of surface
S2017abnMembrane, Nets & Shells 5
Lecture 13
Applied Architectural Structures
ARCH 631
Membrane and Net Structures
• tensile stress and
tangential shear stresses occur
S2017abnMembrane, Nets & Shells 6
Lecture 13
Applied Architectural Structures
ARCH 631
Pneumatic Structures
• internal pressure
– air-supported:
entire volume
– air-inflated: cavities
• ribs
• dual walls
S2017abnMembrane, Nets & Shells 7
Lecture 13
Applied Architectural Structures
ARCH 631
Air-Supported Structures
• pressure slightly
higher than
atmospheric
• light loads
• greater spans than
air-inflated
S2017abnMembrane, Nets & Shells 8
Lecture 13
Applied Architectural Structures
ARCH 631
Air-Inflated Structures
• higher degree of
pressurization
• pressure doesn’t
directly balance
loads
• buckling or folding
results in collapse
• flexibility in space
S2017abnMembrane, Nets & Shells 9
Lecture 13
Applied Architectural Structures
ARCH 631
Loads & Behavior
• snow accumulation
– shape
– heat loss
• avoid large
concentrated loads
• wind loads
– suction
– tension
– “buckling”
S2017abnMembrane, Nets & Shells 10
Lecture 13
Applied Architectural Structures
ARCH 631
Membrane Stresses
• pressure is constantly applied stress
S2017abnMembrane, Nets & Shells 11
Lecture 13
Applied Architectural Structures
ARCH 631
Membrane Stresses• enough pressure to prevent folding