722.2.4.3 Tie and spiral reinforcement.
BC § 722.2.4.3
For concrete columns made with concrete having a specified compressive strength, f'c , greater than 12,000 psi (82.7 MPa), tie and spiral reinforcement shall comply with the following: 1. The free ends of rectangular ties shall terminate with a 135-degree (2.4 rad) standard tie hook.
2.The free ends of circular ties shall terminate with a 90-degree (1.6 rad) standard tie hook.
3.The free ends of spirals, including at lap splices, shall terminate with a 90-degree (1.6 rad) standard tie hook. The hook extension at the free end of ties and spirals shall be the larger of six bar diameters and the extension required by Section 7.1.3 of ACI 318. Hooks shall project into the core of the column.
