What is the role of reinforcement in resisting tensile stresses in concrete?

• A. Reinforcement increases compressive strength.
• B. Steel reinforcement carries tensile stresses where concrete is weak in tension.
• C. Concrete carries tensile stresses more than steel.
• D. Reinforcement prevents moisture intrusion.

Answer: (B)

Concrete is strong in compression but weak in tension, so reinforcement is used to carry the tensile stresses where concrete would crack. Steel reinforcement has high tensile strength and bonds well with concrete, allowing the two materials to act together as a single system. In bending, the tension zone at the bottom of a beam is resisted by the steel, while the compression zone at the top relies mainly on concrete. This composite action delays cracking, increases ductility, and raises the member’s overall strength.

That’s why the statement about steel carrying the tensile stresses where concrete is weak in tension is the best description. The other ideas don’t fit: reinforcement mainly enhances tensile capacity, not compressive strength; concrete does not carry more tensile stress than steel; and preventing moisture intrusion is not the primary role of reinforcement.