Ground pressure calculator: equal-track area, configured weight and reference ratios

It divides entered working weight by a simplified total contact area for the selected number of equal rectangular tracks. The resulting average is a comparison under those assumptions, not a prediction that a machine floats or sinks. It cannot establish safe access, bearing design, settlement, surface damage or the strength of a buried structure.

Use the machine’s actual working configuration and the relevant attachments and load, checking what a published figure already includes. A bare or differently equipped operating mass cannot automatically describe the planned work. Do not count included fuel, attachments or other items twice, and retain the source and basis when a specification rather than a measured mass is used.

Use the ground-contact length for the stated condition, rather than the complete track-frame or machine length. The ideal model treats that length and shoe width as a rectangle. A longer visible assembly does not establish that all of it carries load on the ground, and different contact assumptions produce a different average even with unchanged weight.

Use two tracks × 12 in width × 108 in contact length to obtain 2,592 in². Divide the expressly assumed 20,000 lb weight by that area to obtain about 7.72 psi. These are hypothetical equal rectangular tracks and a supplied weight, not a specification or field measurement for a named crawler.

Holding the example’s other assumptions constant, two × 18 × 108 gives 3,888 in², and 20,000 divided by that area is about 5.14 psi. This isolates an area effect in the model. It does not claim that fitting wider real shoes leaves machine weight, geometry, support or transport dimensions unchanged.

The Deere 245 P-Tier brochure lists 700 mm shoes with 45 kPa pressure, 25,500 kg operating weight and 3.09 m overall width, versus 800 mm shoes with 40 kPa, 25,800 kg and 3.19 m width. Retain the complete documented configuration and source notes. A one-dimension model edit is not a replacement manufacturer specification.

The form assumes identical entered widths and contact lengths for all selected tracks. Actual front and rear assemblies or loading can differ. Identify those limitations rather than treating the four-track count as proof that the model represents unequal geometry, articulation or load distribution of every machine with four independent track assemblies.

Attachment position, unequal track loading, local roller reactions, turning and dynamic effects can change the loads transmitted to the surface. The nominal average does not show each peak or local condition. Two machines with the same calculated average can therefore have different support demands and ground response during the actual operation.

Use it only as an identified numerical reference whose design applicability must be established elsewhere. For an expressly assumed 10 psi reference, the 7.72 psi example is about 77% of that number. This does not prove a 23% safe reserve or a valid safety factor; a soil or structure value needs its actual loading and assessment basis.

The existing form uses zero to omit that numerical reference comparison; it is not a claim that actual soil bearing capacity is zero. The nominal calculation still depends on the entered weight and geometry. Do not invent a positive ground value merely to obtain a ratio, and do not treat an omitted reference as a completed support assessment.

Pounds divided by square inches produce psi; one psi is about 6.895 kPa. Convert shoe and contact dimensions consistently before using the area, with millimetres divided by 25.4 for inches. Unit conversion cannot resolve an inappropriate weight, length or ground reference, so retain the physical input basis as well as the numbers.

Assess actual layers, voids, edges, water, buried facilities and structures, with the planned loading and operating conditions. A mat’s outer area also does not automatically establish effective support. Use the appropriate ground and machine assessment instead of interpreting a lower average or favorable ratio as permission to enter, lift or travel on the site.