ABSTRACT
The expression relating strains in the reinforcement in tension and the maximum compressive strain still holds:
=
+
ε
ε ε (17.4)
The expression for equilibrium of forces requires a new term describing the force carried by the reinforcement in compression (Cs):
T = Cc + Cs (17.5)
where T is the tensile force, T = As · fsy (if the steel in tension yields); Cc, the compressive force in the concrete, = k1 · 0.85 · fcʹ · (b · kud – Aʹs) (we subtract the area A′s because it is occupied by steel); and Cs is the compressive force resisted by steel, Cs = Aʹs · fsʹ.
