Thermal conductivity against densityHigher and further left: spreads more heat for its weightThermal expansion against thermal conductivityLower and further right: warps less when heated
Sources7 documents: National Ready Mixed Concrete Association, Federal Highway Administration, Oak Ridge National Laboratory, USDA Forest Products Laboratory, National Institute of Standards and Technology
Values for
Cast. Normal-weight portland cement concrete, strength class f'c = 4000 psi (28 MPa) per NRMCA CIP 35; density NRMCA CIP 36; thermal conductivity USDA FPL Wood Handbook; service temperature ORNL/NRC review
1
CIP 35: Testing Compressive Strength of ConcreteNational Ready Mixed Concrete Associationarchived copyCompressive strength: specified compressive strength class (f'c), not a measured typical
CIP 36: Structural Lightweight ConcreteNational Ready Mixed Concrete Associationarchived copyDensity: range for normalweight concrete
4
The Effect of Elevated Temperature on Concrete Materials and Structures: A Literature Review (ORNL/TM-2005/553)Oak Ridge National Laboratoryarchived copyPoisson's ratio: general range at normal ambient conditions (overall 0.11-0.32)Max service temperature: code long-term temperature limit (ASME Code, concrete containments)
5
Wood Handbook (FPL-GTR-282), Chapter 4: Moisture Relations and Physical Properties of WoodUSDA Forest Products LaboratoryThermal conductivity: typical (comparative value)
6
Thermal Coefficient of Portland Cement ConcreteFederal Highway AdministrationThermal expansion: typical range for portland cement concrete (aggregate dependent)
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Best Practice Guidelines for Structural Fire Resistance Design of Concrete and Steel Buildings (TN 1681)National Institute of Standards and Technologyarchived copySpecific heat: typical (NIST guidance for thermal analysis)
Concrete has a thermal conductivity of 0.9 W/m·K (0.52 BTU/hr·ft·°F). Basis: typical (comparative value). Source: USDA Forest Products Laboratory, Wood Handbook (FPL-GTR-282), Chapter 4: Moisture Relations and Physical Properties of Wood.
Specific heat of Concrete
The specific heat capacity of Concrete is 900 J/kg·K (0.215 BTU/lb·°F). Basis: typical (NIST guidance for thermal analysis). Source: National Institute of Standards and Technology, Best Practice Guidelines for Structural Fire Resistance Design of Concrete and Steel Buildings (TN 1681)archived copy.
Coefficient of thermal expansion of Concrete
Concrete expands 8–12 µm/m·K (4.44–6.67 µin/in·°F): a 100 mm part grows 50 µm over a 50 °C rise. Basis: typical range for portland cement concrete (aggregate dependent). Source: Federal Highway Administration, Thermal Coefficient of Portland Cement Concrete.
Thermal diffusivity of Concrete
Computed from the conductivity, density and specific heat (k / ρc): 0.431 mm²/s, how fast a temperature change spreads through it.
Maximum service temperature of Concrete
The maximum service temperature of Concrete is 65 °C (149 °F). Basis: code long-term temperature limit (ASME Code, concrete containments). Source: Oak Ridge National Laboratory, The Effect of Elevated Temperature on Concrete Materials and Structures: A Literature Review (ORNL/TM-2005/553)archived copy.