What is the density of reinforced concrete?

2,500 kg/m³ (2,300–2,600), or 2.50 g/cm³.

Does reinforced concrete float?

No. At 2,500 kg/m³ it is denser than water.

Reinforced concrete

Density of reinforced concrete

2,500 kg/m³ (2,300–2,600)

2.50 g/cm³ · 156.1 lb/ft³

About 100 kg/m³ heavier than plain concrete because of the steel, which typically occupies 1-2% of the volume. The tensile figures here are still the concrete's: the reinforcement does not stop concrete cracking, it takes over once it has cracked, which is why hairline cracks in a reinforced slab are normal rather than a defect. The failure mode that matters is carbonation and chloride attack reaching the bars — rusting steel expands about six times and spalls the cover off, which is why cover depth is specified so carefully.

Properties

Density: 2,500 kg/m³ (2,300–2,600) — 2.50 g/cm³
Tensile strength: 2–5 MPa
Young's modulus: 30 GPa
Thermal conductivity: 1.7 W/(m·K)
Thermal expansion: 10 µm/(m·K)
Floats in water: No
Magnetic: No

What it is used for

Building frames, floors and columns
Bridges and viaducts
Retaining walls and basements
Precast panels and beams

How it compares

Water is 1,000 kg/m³. Anything with a shorter bar than water floats in it.

air 1.2 kg/m³

expanded polystyrene foam 20 kg/m³

rigid polyurethane foam 40 kg/m³

Water — the float line 1,000 kg/m³

reinforced concrete 2,500 kg/m³

tungsten 19,250 kg/m³

gold 19,300 kg/m³

platinum 21,450 kg/m³

Water is 1,000 kg/m³. Anything below that floats.
Material	Density	Relative to water
rigid polyurethane foam	40 kg/m³	0.04×
expanded polystyrene foam	20 kg/m³	0.02×
air	1.2 kg/m³	0.00×
reinforced concrete ←	2,500 kg/m³	2.50×
platinum	21,450 kg/m³	21.45×
gold	19,300 kg/m³	19.30×
tungsten	19,250 kg/m³	19.25×

Does it rust?

Reinforced concrete contains no iron, so it cannot rust. Whether it degrades depends on the material, not on oxidation.

Is it magnetic?

Reinforced concrete is not a metal and has no ferromagnetic response.

Common questions

What is the density of reinforced concrete?: 2,500 kg/m³ (2,300–2,600), or 2.50 g/cm³.
Does reinforced concrete float?: No. At 2,500 kg/m³ it is denser than water.
Is reinforced concrete magnetic?: Reinforced concrete is not a metal and has no ferromagnetic response.

Does reinforced concrete float? No
Concrete 2,400 kg/m³
Brick 1,900 kg/m³
Gypsum board (drywall) 700 kg/m³
Tungsten carbide 14,900 kg/m³
Graphite 2,200 kg/m³
Porcelain 2,400 kg/m³
Plaster 1,100 kg/m³
Silicon carbide 3,210 kg/m³

Sources

Typical range compiled from manufacturer specifications — At One Place

How these figures are compiled and checked