Acceleration-sensitive nonstructural compo-
nent: A nonstructural component that is sensitive to,
and subject to, damage from inertial loading.
Acceptance criteria: Limiting values of properties
such as drift, strength demand, and inelastic deformation
used to determine the acceptability of a component at a
given performance level.
Action: An internal moment, shear, torque, axial load,
deformation, displacement, or rotation corresponding to
a displacement due to a structural degree of freedom;
designated as force- or deformation-controlled.
Active Fault: A fault for which there is an average his-
toric slip rate of 1 mm per year or more, and evidence of
seismic activity within Holocene times (past 11,000
Adjusted Resistance: The reference resistance
adjusted to include the effects of applicable adjustment
factors resulting from end use and other modifying fac-
tors excluding time-effect adjustments, which are con-
sidered separately and not included.
Aspect ratio: Ratio of height to width for shear walls
and span to width for horizontal diaphragms.
Assembly: Two or more interconnected components.
Balloon framing: Continuous stud framing from sill
to roof, with intervening floor joists nailed to studs and
supported by a let-in ribbon.
Base: The level at which earthquake effects are
imparted to the building.
Beam: A structural member whose primary function is
to carry loads transverse to its longitudinal axis.
Bearing wall: A wall that supports gravity loads of at
least 200 pounds per lineal foot from floors and/or roofs.
Bed joint: The horizontal layer of mortar on which a
masonry unit is laid.
Boundary component (boundary member): A
member at the perimeter (edge or opening) of a shear
wall or horizontal diaphragm that provides tensile and/or
Braced frame: A vertical lateral-force-resisting ele-
ment consisting of vertical, horizontal, and diagonal
components joined by concentric or eccentric connec-
BSE-1: Basic Safety Earthquake-1, t