Understanding Floor Loads
Key factors affecting floor design.
- Live Load Occupancy weight.
- Dead Load Structure weight.
- Span Support distance.
- System Floor type.
Load Analysis
- Dead Loads Floor finish: 1-4 psf. Subfloor: 2-4 psf. Framing: 10-15 psf. MEP: 4-8 psf. Ceiling: 5-10 psf. Total range: 25-50 psf.
- Live Loads Residential: 40 psf. Office: 50-100 psf. Assembly: 100 psf. Storage: 125-250 psf. Reduction factor: 0.4-0.6 (ASCE 7).
- Special Loads Equipment: 200-1000 lbs. Partition: 15-20 psf. Impact: 1.15-1.25×. Vibration: 0.5%g max. Seismic: 0.2-1.0×DL.
Structural Capacity
- Design Limits Ultimate strength: 2.5-3.0×service. Allowable stress: 0.6×yield. Safety factor: 1.5-2.0. Load combinations: ASCE 7-16. Duration factor: 0.6-1.0.
- Material Properties Concrete: f'c 3-5 ksi. Steel: Fy 36-50 ksi. Wood: Fb 1000-3000 psi. Composite action: 0-75%. System factor: 1.1-1.3.
- Support Conditions Bearing capacity: 1500-4000 psf. Edge restraint: 0-100%. Load sharing: 40-60%. Connection efficiency: 80-95%. End fixity: 0-1.0.
Performance Criteria
- Serviceability Deflection: L/360-L/480. Vibration: 8-15 Hz. Crack width: 0.016". Camber: L/240-L/180. Long-term creep: 1.5-2.0×.
- Durability Requirements Fire rating: 1-3 hr. Moisture exposure: Class 1-3. Chemical resistance: pH 5-9. Temperature range: 40-140°F. Service life: 50-100 years.
- Maintenance Factors Inspection interval: 2-5 years. Load testing: 1.5×design. Monitoring points: 5-10. Documentation: as-built ±1/8". Review cycle: 10 years.
System Integration
- MEP Coordination Penetration size: 1/3 depth max. Sleeve clearance: 1". Support spacing: 4-8 ft. Equipment pads: 1.5×load. Isolation: STC 50-60.
- Architectural Interface Floor thickness: 8-24". Finish tolerance: ±1/8". Joint spacing: 20-30 ft. Perimeter gaps: 1/2". Level variation: L/1000.
- Construction Sequence Cure time: 7-28 days. Loading stages: 3-5. Shore removal: 70% strength. QC points: 7-10. Documentation: ASTM E1155.