A Grade 40 steel reinforcing bar is embedded along the axis

A Grade 40 steel reinforcing bar is embedded along the axis of a concrete cylinder with f’c = 4000 psi. The resulting composite member is subjected to an increasing tension force (along the axis of the cylinder). Assuming perfect bond (strain compatibility) between the concrete and steel, which will occur first: yield of the bar or cracking of the concrete? Why?

Solution

Reinforcing bar is embedded along the axis of a concrete cylinder and the member is subjected to an increasing tension force. Grade 40 steel (yield strength of 40,000 psi) and f\'c= 4000psi.

Because of the increasing tension force, between the concrete and steel, cracking of the concrete will occur first, as the concrete is week in resisting tensile force when compared to steel. The tensile strength of grade 40 steel is greater than the concrete with f\'c-4000psi.