About this tool Calculate the minimum bund height and material volume for haul road edge protection in quarries and mines. Enter the wheel diameter of the largest vehicle using the road — the tool calculates the required bund height, trapezoidal cross-section, and total volume.
Includes presets for common vehicles from pickups to large rigid dump trucks (CAT 793). Adjustable bund side slope angle for different fill materials.
Per Quarries Regulations 1999 (Regulation 30) and HSE Approved Code of Practice L118: bunds must be at least as high as the axle height (half the wheel diameter) of the largest vehicle.
How to use this tool 1. Select a vehicle preset or enter wheel diameter — the tyre diameter of the largest vehicle on the haul road.
2. Set the bund side slope — typically 35–45° for compacted fill.
3. Enter bund length (optional) — to calculate total volume of material required.
Technical information Minimum height = wheel diameter / 2 (axle height)
Cross-section = trapezoidal: A = ((top + base) / 2) × height
Base width = top width + 2 × (height / tan(slope angle)). Top width is the greater of 1.0 m or the bund height.
Limitations This calculates the minimum regulatory height. Bunds at tip edges, ramps, and high-risk locations should be higher — typically 1.5× axle height. Always conduct a site-specific risk assessment.
Does not account for compaction, settlement, or erosion of the bund material over time. Bunds should be regularly inspected and maintained.
The trapezoidal cross-section is a simplification. Actual bund profiles depend on construction method and fill material.
Revision history 4 August 2026: Initial release
Disclaimer This tool is provided for educational and general information purposes only. It is not a substitute for professional engineering advice, design or verification.
Diggy and its contributors are not licensed engineering consultants and no results generated by this tool should be used directly for construction, design or safety-critical decisions.
All values and outputs are based on published empirical correlations and should be independently checked and confirmed by a qualified geotechnical engineer before use.
By using this tool, you accept full responsibility for how you interpret and apply the information provided.
Spotted an error? Let us know .
