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ACI 318-19 : Beam Reinforcement Detailing
TSC 2018 : Longitudinal Reinforcement Detailing for Beams. Transverse Reinforcement Detailing for Beams.
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Notation in ACI 318-19
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
√fc‘ = square root of specified compressive strength of concrete, psi
fy = specified yield strength of nonprestressed reinforcement,psi
Ktr = transverse reinforcement index, in.
ld = development length in tension of deformed bar, deformed wire, plain and deformed welded wire reinforcement, or pretensioned strand, in.
s = center-to-center spacing of items, such as longitudinal reinforcement, transverse reinforcement, tendons, or anchors, in.
ψe = factor used to modify development length based on reinforcement coating
ψg = factor used to modify development length based on grade of reinforcement
ψs = factor used to modify development length based on reinforcement size
ψt = factor used to modify development length for casting location in tension
λ = modification factor to reflect the reduced mechanical properties of lightweight concrete relative to normalweight concrete of the same compressive strength
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