Asce-05

P1: JsY
ASCE003-06.tex

ASCE003/SIE-v1.cls

October 10, 2005

Chapter 6

WIND LOADS
6.1 GENERAL
6.1.1 Scope. Buildings and other structures, including the Main
Wind-Force Resisting System (MWFRS) and all components and
cladding thereof, shall be designed and constructed to resist wind
loads as specified herein.
6.1.2 Allowed Procedures. The design wind loads for buildings
and otherstructures, including the MWFRS and component and
cladding elements thereof, shall be determined using one of the
following procedures: (1) Method 1—Simplified Procedure as
specified in Section 6.4 for buildings meeting the requirements
specified therein; (2) Method 2—Analytical Procedure as specified in Section 6.5 for buildings meeting the requirements specified therein; (3) Method 3—Wind TunnelProcedure as specified
in Section 6.6.
6.1.3 Wind Pressures Acting on Opposite Faces of Each
Building Surface. In the calculation of design wind loads for
the MWFRS and for components and cladding for buildings, the
algebraic sum of the pressures acting on opposite faces of each
building surface shall be taken into account.
6.1.4 Minimum Design Wind Loading. The design wind load,determined by any one of the procedures specified in Section 6.1.2, shall be not less than specified in this section.
6.1.4.1 Main Wind-Force Resisting System. The wind load to
be used in the design of the MWFRS for an enclosed or partially
enclosed building or other structure shall not be less than 10 lb/ft2
(0.48 kN/m2 ) multiplied by the area of the building or structure
projected onto a verticalplane normal to the assumed wind direction. The design wind force for open buildings and other structures shall be not less than 10 lb/ft2 (0.48 kN/m2 ) multiplied by the
area A f .
6.1.4.2 Components and Cladding. The design wind pressure
for components and cladding of buildings shall not be less than
a net pressure of 10 lb/ft2 (0.48 kN/m2 ) acting in either direction
normal to the surface.6.2 DEFINITIONS
The following definitions apply only to the provisions of
Chapter 6:
APPROVED: Acceptable to the authority having jurisdiction.
BASIC WIND SPEED, V: Three-second gust speed at 33 ft
(10 m) above the ground in Exposure C (see Section 6.5.6.3) as
determined in accordance with Section 6.5.4.
BUILDING, ENCLOSED: A building that does not comply
with the requirements for open orpartially enclosed buildings.
BUILDING ENVELOPE: Cladding, roofing, exterior walls,
glazing, door assemblies, window assemblies, skylight assemblies, and other components enclosing the building.
Minimum Design Loads for Buildings and Other Structures

BUILDING AND OTHER STRUCTURE, FLEXIBLE:
Slender buildings and other structures that have a fundamental
natural frequency less than 1 Hz.BUILDING, LOW-RISE: Enclosed or partially enclosed
buildings that comply with the following conditions:
1. Mean roof height h less than or equal to 60 ft (18 m).
2. Mean roof height h does not exceed least horizontal dimension.
BUILDING, OPEN: A building having each wall at least
80 percent open. This condition is expressed for each wall by
the equation Ao ≥ 0.8 A g where
Ao = total area ofopenings in a wall that receives positive
external pressure, in ft2 (m2 )
A g = the gross area of that wall in which Ao is identified, in
ft2 (m2 )
BUILDING, PARTIALLY ENCLOSED: A building that
complies with both of the following conditions:
1. The total area of openings in a wall that receives positive
external pressure exceeds the sum of the areas of openings
in the balance of the buildingenvelope (walls and roof ) by
more than 10 percent.
2. The total area of openings in a wall that receives positive
external pressure exceeds 4 ft2 (0.37 m2 ) or 1 percent of the
area of that wall, whichever is smaller, and the percentage
of openings in the balance of the building envelope does not
exceed 20 percent.
These conditions are expressed by the following equations:
1. Ao > 1.10 Aoi...