What step is typically taken to ensure rebar has clean, oil-free surfaces before concrete pour?

• A. Cleaning or degreasing the bars and inspecting for contaminants.
• B. Coating bars with oil before pour.
• C. Relying on the concrete to clean the bars.
• D. Welding immediately without cleaning.

Answer: (A)

Bond between concrete and reinforcing steel depends on having clean, oil-free surfaces. Any oil, grease, dirt, or form-release residue on the bars creates a film that blocks the cement paste from bonding with the steel, which can weaken shear transfer and invite corrosion. The right step is to clean or degrease the bars and inspect for contaminants before pouring, ensuring the surface is dry and free of residues. Coating the bars with oil would add the very barrier you’re trying to avoid. Relying on the concrete to clean the bars is not reliable, and welding without cleaning could introduce defects.