Page Comparison

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Symbols

d_b = nominal diameter of bar, wire, or prestressing strand, in
A_ch = cross-sectional area of a member measured to the outside edges of transverse reinforcement, in.²
f'_c = specified comprehensive strength of concrete, psi
f_yt = specified yield strength of transverse reinforcement,psi
A_g = gross area of the 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)

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Ties

Ties apply a closed loop of the deformed bar, which satisfies the rules:

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(a) Ends overlap by at least 6 in.
(b) Ends terminate with standard hooks in accordance with ACI 25.3.2 that engage a longitudinal bar
(c) Overlaps at ends of adjacent circular ties are staggered around the perimeter, enclosing the longitudinal bars

Hoop

Hoops consist of a closed or continuously wound tie with several reinforcement elements, each having seismic hooks at both ends.
The ends of the hoop reinforcement elements are anchored using seismic hooks that conform to ACI 25.3.4 and engage a longitudinal bar.

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