stresses from gravity forces, and bending moments
gravity and lateral loads solely through resistance of
from combined gravity and lateral forces.
the masonry materials.
Reinforced Masonry (RM) Walls: A masonry wall
Wythe: A continuous vertical section of a wall, one
that is reinforced in both the vertical and horizontal
masonry unit in thickness.
directions. Reinforced walls are assumed to resist
Maximum Considered Earthquake Ground Motion:
compression and the reinforcing steel in tension or
The most severe earthquake effects considered by this
compression. Reinforced masonry is partially grouted
document as defined in Chapter 3.
or fully grouted.
Moment Frames:
Intermediate Reinforced Masonry Walls Shear
Walls: To be designed in accordance with
Intermediate Moment Frames (IMF): Moment
Section 11.11.4 of FEMA 302.
frames of reinforced concrete or structural steel
conforming to detailing requirements that provide
Masonry continued:
capability for moderate inelastic rotation of the
beam/column joint.
Special Reinforces Masonry Shear Walls: To
Ordinary Moment Frames (OMF): Moment frames
be designed in accordance with Section 11.11.5
of FEMA 302.
of reinforced concrete or structural steel conforming
to limited detailing requirements that provide
Running Bond: A pattern of masonry where the
capability for nominal inelastic rotation of the beam
column joint.
head joints are staggered between adjacent courses by
more than a third of the length of a masonry unit.
Special Moment Frames (SMF): Moment Frames of
Also refers to the placement of masonry units such
that head joints in successive courses are horizontally
reinforced concrete or structural steel conforming to
offset at least one-quarter the unit length.
detailing requirements that provide capability for
significant inelastic rotation of the beam/column joint.
Solid Masonry Unit: A masonry unit whose net
Eccentric Braced Frame (EBF): A diagonal braced
cross-sectional area in every plane parallel to the
bearing surface is 75% or more of the gross cross-
frame in which at least one end of each diagonal
sectional area in the same plane.
bracing member connects to a beam a short distance
from either a beam-to-column connection or another
Solid Wall or Solid Infill Panel: A wall or infill
brace end.
panel with openings not exceeding 5% of the wall
Nonstructural Performance Level: A limiting damage
surface area. The maximum length or height of an
opening in a solid wall must not exceed 10% of the
state for nonstructural building components used to define
wall width or story height. Openings in a solid wall or
Performance Objectives.
infill panel must be located within the middle 50% of
Partition: A nonstructural interior wall that spans from
a wall length and story height, and must not be
contiguous with adjacent openings.
floor to ceiling, to the floor or roof structure immediately
above, or to subsidiary structural members attached to the
Stack Bond: In contrast to running bond, usually a
structure above. A partition may receive lateral support
placement of units such that the head joints in
from the floor above, but shall be designed and detailed so
successive courses are aligned vertically.
as not to provide lateral or vertical support for that floor.
Transverse Wall: A wall that is oriented transverse
P-Delta Effect: The secondary effect on shears and
to the in-plane shear walls, and resists lateral forces
moments of frame members due to the action of the vertical
applied normal to its plane. Also known as an out-of-
loads induced by displacement of the building frame
plane wall.
resulting from the design loads.
Unreinforced Masonry (URM) Wall: A masonry
Primary Component: Those components that are required
wall containing less than the minimum amounts of
as part of the building' lateral-force-resisting system (as
s
reinforcement as defined for reinforced masonry
contrasted to secondary components).
(RM) walls. An unreinforced wall is assumed to resist
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