Model stacked materials with realistic site load factors. Compare pressure against allowable bearing limits today. Download results instantly for reports and field checks anywhere.
| Scenario | Unit weight | Units/layer | Layers | Footprint | Dynamic | Allowable pressure | Estimated bearing | Safety factor |
|---|---|---|---|---|---|---|---|---|
| Bagged material on pallet | 25 kg | 8 | 5 | 1.20 m × 1.00 m | 1.20 | 120 kPa | ~82 kPa | ~1.46 |
| Concrete blocks stacked | 18 kg | 10 | 7 | 1.40 m × 1.20 m | 1.10 | 90 kPa | ~77 kPa | ~1.17 |
| Crated equipment storage | 60 kg | 4 | 4 | 1.50 m × 1.20 m | 1.30 | 100 kPa | ~68 kPa | ~1.47 |
1) Total units
Total Units = Units per Layer × Layers
2) Gross stack weight
Gross Weight = (Total Units × Unit Weight) + Additional Dead Load
3) Design weight and design load
Design Weight = Gross Weight × Dynamic Factor
Design Load (kN) = Design Weight (kg) × 9.80665 ÷ 1000
4) Bearing pressure
Footprint Area = Length × Width
Bearing Pressure (kPa) = Design Load (kN) ÷ Footprint Area (m²)
5) Safety factor (bearing)
Safety Factor = Allowable Pressure ÷ Bearing Pressure
Temporary storage stacks can exceed floor or packaging capacity long before they look unsafe. A quick bearing and unit-load check reduces crushing, settlement, and rehandling. It also supports safer access routes for forklifts and clear documentation for supervisors and inspectors. When trades overlap, limits prevent hidden hazards.
Accurate unit weight, units per layer, and layer count establish gross stack weight. Footprint dimensions define contact area, which controls bearing pressure. The dynamic factor accounts for handling impacts, vibration, and short-term overloads, while the distribution factor represents how much load the bottom layer carries. Include pallet, straps, and blocking as dead load so the design reflects real conditions.
Bearing pressure equals design load divided by footprint area. Compare it with the allowable pressure from floor ratings, dunnage specifications, or packaging limits. The safety factor is allowable divided by actual. Values above 1.00 indicate capacity margin; values near 1.00 need control of moisture, creep, and uneven contact. If allowable pressure is uncertain, adopt a conservative value and confirm with site guidance.
If the check fails, reduce layers, increase footprint area with spreader timbers, or move the stack to a higher-capacity slab zone. Consider splitting one tall stack into two shorter stacks to reduce handling risk. For fragile goods, lower the dynamic factor only when movement is eliminated and contact is uniform. Use the “max layers” output as a planning ceiling.
Confirm the true contact area, not nominal pallet size, especially on irregular ground. Check for point supports, damaged pallets, and soft insulation layers that concentrate stress. Monitor stacks after rain or temperature changes. Record inputs and outputs with the CSV or PDF tools for audits and daily reports. Pair the calculation with simple controls: labeling stack heights, training operators on gentle placement, and keeping heavy stacks away from slab edges.
It increases the stack weight to reflect handling shocks, vibration, or minor impacts. Use 1.0 for static storage, and higher values when forklifts move or place the load during the shift.
Use the lowest verified limit among slab ratings, floor loading charts, packaging specifications, and dunnage capacity. If you cannot confirm a value, adopt a conservative assumption and get site engineering approval.
Small footprints concentrate load. Even moderate weights can produce high pressure on narrow skids, point supports, or uneven ground. Increasing contact area often reduces pressure more effectively than reducing one layer.
It estimates the share of total design load carried by the bottom layer. Keep it at 1.0 unless you have verified load sharing through racking, framing, or engineered supports.
No. Treat results as a planning check for field stacking. Packaging compressive strength, creep, moisture effects, and damage history must still be validated with supplier data or formal testing.
Yes. After calculating, download the CSV or PDF from the result section. Keep the file with your lift plan, laydown map, or daily report to show assumptions and limits.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.