Rebar surfaces should be clean, free from oil stains, paint污, rust skin, and scales. For water rust and color rust on rebar surfaces, special treatment is not required.
Rebars should be straight with no local bends, and the deviation of the centerline from the straight line should not exceed 1% of its total length. Coiled rebars or rebars that have been bent should be straightened before use.

In accordance with the provisions of the "Code for Acceptance of Construction Quality of Concrete Structures," the rusting of steel rebars must not affect the cross-sectional area of the rebars, and the surface of the rebars must not have scales of rust resembling fish scales.

The surface of de-rusted rebar should exhibit different colors and finishes, depending on the diameter of the rebar. For rebar with a diameter less than 20mm, the surface should appear uniformly bright silver after de-rusting; for rebar with a diameter between 20mm and 40mm, the surface should be silver without any rust powder or stains; for rebar with a diameter greater than 40mm, the surface should be bright silver and smooth with no rust spots.

Rust removal methods include mechanical cleaning, chemical cleaning, and blasting cleaning. Rust removal should be conducted prior to concrete pouring to ensure that the rebar surface is free of corrosion.