Pound-force per Cubic Foot (lbf/ft³): Definition, Unit of Specific Weight and Conversions
Pound-force per cubic foot (symbol: lbf/ft³) is an Imperial and US customary unit of specific weight. It measures the weight, or gravitational force, of a material contained within one cubic foot of volume. Specific weight differs from mass density because it expresses force per unit volume rather than mass per unit volume.
Definition
One pound-force per cubic foot represents the specific weight of a material exerting a gravitational force of one pound-force over a volume of one cubic foot.
1 lbf/ft³ = 157.087463 N/m³
Where is Pound-force per Cubic Foot Used?
- Civil engineering
- Structural engineering
- Geotechnical engineering
- Hydraulic engineering
- Construction
- Material testing
- North American engineering standards
Relationship to Other Specific Weight Units
- 1 lbf/ft³ = 157.087463 N/m³
- 1 lbf/ft³ = 0.157087463 kN/m³
- 1 lbf/ft³ ≈ 16.018463 kgf/m³
- 1 lbf/ft³ = 0.0005787037 lbf/in³
Related Conversions
- Pound-force per Cubic Foot to Newton per Cubic Meter
- Pound-force per Cubic Foot to Kilonewton per Cubic Meter
- Pound-force per Cubic Foot to Kilogram-force per Cubic Meter
- Pound-force per Cubic Foot to Pound-force per Cubic Inch
- Newton per Cubic Meter to Pound-force per Cubic Foot
Real-World Examples
Pound-force per cubic foot is commonly used in North American engineering to specify the specific weight of construction materials such as concrete, soil, asphalt, timber, and water. For example, water has a specific weight of approximately 62.4 lbf/ft³ under standard conditions.
Frequently Asked Questions
Is pound-force per cubic foot an SI unit?
No. It is an Imperial and US customary unit. The SI unit of specific weight is the newton per cubic meter (N/m³).
What does lbf/ft³ measure?
It measures the weight (gravitational force) of a material contained within one cubic foot of volume.
Where is lbf/ft³ commonly used?
It is widely used in civil engineering, geotechnical engineering, hydraulic engineering, and construction in countries using the Imperial or US customary system.
Conclusion
Pound-force per cubic foot is one of the most widely used Imperial units of specific weight. Although SI units are preferred internationally, lbf/ft³ remains a standard engineering unit in the United States and other regions using the Imperial measurement system.