This reinforcement consists of stirrups or U-shaped insets that embrace horizontal reinforcement.
Symbols:
Av - cross-section of horizontal reinforcement (through two arms).
sv - spacing of vertical reinforcement.
The percent of vertical reinforcement equals
.
It must be smaller than 0.75 * τ ou / f e / γ s , (the minimum value = ρ v = 0.8 / f e ).
Vertical reinforcement should be evenly distributed (uniform load) for the following.