Overview
ISO 16754:2008 - Earth‑moving machinery - Determination of average ground contact pressure for crawler machines - specifies a uniform method to calculate the average ground contact pressure of self‑propelled and towed crawler (track‑laying) earth‑moving machines (see ISO 6165). The calculated value is intended for comparing different machine models on soft surfaces with empty equipment or attachment, not for predicting exact in‑service pressures.
Key topics and requirements
- Scope and purpose: Method applies to crawler machines on soft surfaces with empty attachments and is for comparison only; actual in‑service pressures vary with load, centre of gravity, terrain, track shoe type/size and surface conditions.
- Input parameters: The calculation uses operating mass (m), number of tracks (n), track shoe width (W4), crawler base (L2) and overall crawler length (L6). Units are defined in the standard (mass in kilograms, dimensions in millimetres; result in kilopascals).
- Calculation: ISO 16754 provides a formula that combines these parameters with gravity (9.807 m/s²) and includes an allowance for some track penetration into the supporting soil (increase in support area). The standard also gives a method to determine L6 from crawler geometry where applicable (conditions include a minimum angle α).
- Configuration and measurement rules: Machines must be in the manufacturer’s standard configuration. References to ISO 6746‑1 define dimensional terms (crawler base, overall crawler length, track shoe width) and ISO 6165 defines machine types.
- Limitations and notes: Alternative methods may be appropriate for some machine families; the average ground contact pressure is comparative only.
Applications and users
- Equipment manufacturers use ISO 16754:2008 to publish comparable ground contact pressure data across product lines and support product specifications.
- Test laboratories and certification bodies apply the method to produce consistent comparative measurements.
- Procurement professionals and fleet managers compare crawler machines for site suitability based on average ground contact pressure.
- R&D and engineering teams use the standard when designing undercarriage geometry to influence contact pressure.
- Note: For site‑specific soil compaction assessments or real‑world operating loads, on‑site measurement and more detailed analysis are required.
Related standards
- ISO 6165 - Basic types and definitions for earth‑moving machinery
- ISO 6746‑1 - Definitions of dimensions and codes (base machine)
- ISO 6016 - Measuring the masses of whole machines
- Referenced: SAE J1309 (related crawler performance and rating procedures)
Keywords: ISO 16754:2008, ground contact pressure, average ground contact pressure, crawler machines, track‑laying, crawler base, track shoe width, operating mass, earth‑moving machinery.