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ACI 318-19 : Transverse Reinforcement (CRD)
TSC 2018 : Transverse Reinforcement Detailing for Columns
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Notation in ACI 318-19
Ag = gross area of concrete section, in.2 For a hollow section, Ag is the area of the concrete only and does not include the area of the void(s)
Ab = area of an individual bar or wire, in.2
bw = width of compression face of member, in.
d = distance from extreme compression fiber to centroid of longitudinal tension reinforcement, in.
dagg = Nominal maximum size of coarse aggregate, in.
db = nominal diameter of bar, wire, or prestressing strand, in
fc'= specified compressive strength of concrete, psi
fy = specified yield strength of nonprestressed reinforcement,psi
h = overall thickness, height, or depth of member, in.
hx = maximum center-to-center spacing of longitudinal bars laterally supported by corners of crossties or hoop legs around the perimeter of a column or wall boundary element, in.
ld = development length in tension of deformed bar, deformed wire, plain and deformed welded wire reinforcement, or pretensioned strand, in.
lo = length, measured from joint face along axis of member, over which special transverse reinforcement must be provided, in.
lu = unsupported length of column or wall, in.
Pu= factored axial force; to be taken as positive for compression and negative for tension, lb
s = center-to-center spacing of items, such as longitudinal reinforcement, transverse reinforcement, tendons, or anchors, in.
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