Minimum Longitudinal Reinforcing

Per ACI 318, 10.5.4 & 7.12,

r_min = 0.0018 " A_s,min = 0.0018 ∙ 180 in ∙ 30 in = 9.72 in²

This will be enforced for both top and bottom bars together (rather than each separately) as explained in Section 4.10.3.

Longitudinal Reinforcing Spacing Limits

Per ACI 318, 10.5.4,

S_max = min(3t_f, 18 in) = 18 in

Minimum number of bars to meet $s_{\max }=\frac{180"-2[3"+0.5(0.75"\left)\right]}{18"}+1=11$

This will be enforced for bottom bars, and also for top bars if they are required as explained in Section 4.10.3.

Design Forces

q_u at right footing edge = 3.85 ksf

q_u at right column edge = 3.85 ksf ∙ (12.57 - 7.50 + 0.75) / 12.57 = 1.78 ksf

q_u at "d" from right column edge = 3.85 ksf ∙ (12.57 - 7.50 + 0.75 + 26.63/12) / 12.57 = 2.46 ksf

One-way shear,

V_u = 15 ∙ (7.50 - 0.75 - 26.63/12) ∙ (3.85 + 2.46) / 2 = 214.4 k

Positive flexure,

M_u = 3.79 ∙ (3.85 + 1.78) ∙ (7.50 - 0.75) ∙ 15 / 2 = 1080.2 k-ft