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ACI 318-19 : /wiki/spaces/T2EB/pages/1804405953
TSC 2018 : TSC Development of Reinforcement
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Symbols in ACI 318-19
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
Ktr = transverse reinforcement index, in.
Atr = total cross-sectional area of all transverse reinforcement within spacing s that crosses the potential plane of splitting through the reinforcement being developed, in.2
db = nominal diameter of bar, wire, or prestressing strand, in
f'c = specified comprehensive strength of concrete, psi
fy = specified yield strength of nonprestressed reinforcement,psi
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.
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