Ground Bearing Pressure Calculator

Calculate ground pressure from equipment weight and track/tire dimensions. Check if your equipment is suitable for soft or sensitive ground conditions.

Pre-filled from: Caterpillar DE50 GC

How the calculation works

Ground bearing pressure is the machine's weight spread over the area in contact with the ground. The calculator turns the weight in tonnes into a force in kilonewtons (tonnes × 9.81) and divides it by the contact area in square metres, giving a pressure in kilopascals (kPa). The result is an average over the whole contact area.

Contact area by equipment type

  • Tracked: track width × track length on the ground × number of tracks (default 2) × 0.75. The 0.75 factor allows for the gaps between track shoes.
  • Wheeled: tyre width × an assumed 0.25 m contact length × number of tyres (default 4).
  • Outriggers: pad area × number of outriggers (default 4). This treats the load as shared equally between the pads.
  • Known contact area: tick the override and enter the total area in square metres to skip the estimate.

Using the calculator

  1. Open it from a Plant Library model page to fill in the operating weight (or gross weight) and the track width and length where the model records them, or enter the figures yourself.
  2. Choose tracked, wheeled or outriggers and enter the contact dimensions in millimetres or square metres.
  3. Read the pressure, the contact area and the rating band, then print the result if needed.

Rating bands

  • Very Low Pressure (under 25 kPa): Suitable for very soft ground (peat, wet clay, sensitive surfaces).
  • Low Pressure (25 to 50 kPa): Suitable for soft to moderate ground conditions.
  • Moderate Pressure (50 to 100 kPa): Suitable for firm ground (compacted clay, gravel).
  • High Pressure (100 to 200 kPa): Requires firm ground (dense gravel, hardstand). Consider bog mats on softer surfaces.
  • Very High Pressure (200 kPa and above): Requires hard surfaces (concrete, rock). Mats or pads required on most soils.

The figure does not account for uneven load across the tracks, slewing or lifting loads, dynamic effects while travelling, or soil moisture. Use it to compare machines and plan mats or platforms, and get a geotechnical assessment where the ground or the lift is critical.

Ground bearing capacity guide

Typical Soil Bearing Capacities

  • Peat / Soft clay (wet)< 25 kPa
  • Soft clay / Silt25–50 kPa
  • Firm clay / Loose sand50–100 kPa
  • Stiff clay / Medium sand100–200 kPa
  • Dense sand / Gravel200–400 kPa
  • Rock / Concrete> 400 kPa

Typical Equipment Ground Pressure

  • Compact excavator (2–5t)20–35 kPa
  • Mid excavator (12–25t)35–55 kPa
  • Large excavator (30–50t)50–75 kPa
  • Crawler dozer (15–40t)40–70 kPa
  • Wheeled loader (10–30t)150–300 kPa

Disclaimer: This calculator provides estimates only. Actual ground pressure varies with load distribution, soil moisture, and operating conditions. Always conduct proper geotechnical assessment for critical applications.

Mitigation Strategies

  • 1.Bog mats / Timber mats: Distribute load over larger area, reduce pressure by 50–70%
  • 2.Wider tracks / Low ground pressure tracks: Factory or aftermarket options
  • 3.Temporary roadways: Geotextile + crushed rock or concrete panels
  • 4.Smaller equipment: Consider multiple passes with lighter machine

Related: transport clearance calculator · excavator specifications · dozer specifications · crane specifications