Density of Reinforced Concrete

ρRC=2400 kg/m3\rho_{\mathrm{RC}} = 2400\ \text{kg/m}^{3}
Value2400 kg/m³
StatusMeasured: ± 100 kg/m³ (0.042 relative)
SourceACI 318, Building Code Requirements for Structural Concrete
CategoriesMaterial PropertiesEngineering & Trademechanics
ρ_c in every density unit
kilogram per cubic meter2,400 kg/m³
gram per cubic centimeter2.4 g/cm³
gram per milliliter2.4 g/mL
kilogram per liter2.4 kg/L
pound per cubic foot149.82711 lb/ft³
pound per US gallon20.028971 lb/gal

Learning zone

Normal-weight plain concrete runs about 2300 kg/m³ (145 lb/ft³); ordinary reinforcement adds roughly 100 kg/m³, which is where the design figure of 2400 kg/m³ or 150 lb/ft³ comes from. Codes let you use 24 kN/m³ as the unit weight for self-weight, and a 150 mm slab therefore loads its supports at about 3.6 kPa (75 psf) before anything is put on it. Self-weight dominates concrete design in a way it never does in steel.

It is not one material. Structural lightweight concrete with expanded shale aggregate runs 1750–1900 kg/m³ and buys back a fifth of the dead load at the cost of stiffness and cost per cubic metre; heavyweight radiation-shielding mixes with magnetite or barite reach 3500 kg/m³ and above. Aggregate type, air entrainment and moisture state all move the figure by a few percent, so weigh a trial batch if you are checking a crane pick or a precast lift, and treat 2400 as a design convention rather than a measurement.