Result

These empirical relations give a sensible starting geometry, not a final design. Burden is the most critical dimension — too small wastes explosive and throws fly-rock, too large leaves toe and coarse fragmentation — and the right ratio depends on rock structure, jointing, water condition and the actual explosive energy, which is why the ratio is editable. The stiffness check matters because a short, stiff bench (height below about twice the burden) resists flexure and breaks poorly at the toe. Powder factor is only a sanity check against typical ranges; real designs are tuned from measured fragmentation and vibration results. Blasting is a regulated, licensed activity: initiation sequencing, delay timing, fly-rock clearance, vibration and air-blast limits, and magazine/transport rules are all outside this tool and are legally mandatory. Never take any output from this page to the field without a certified blasting engineer's approval.