Start with Geometric Basket Volume
For a rectangular basket, nominal fill volume is length multiplied by width multiplied by height. A 2 m by 1 m by 1 m basket therefore has a geometric volume of 2 cubic metres. Add the volumes of every basket and mattress in the schedule, using the actual dimensions rather than a convenient average. Separate different unit types because thin mattresses, curved work, steps, and irregular transitions may have different fill efficiency and stone grading. Verify whether drawings quote external or internal dimensions and whether foundation embedment is included. A clean spreadsheet by structure and chainage prevents the most common error: multiplying one typical basket by an inaccurate total count.
Convert Volume to Stone Tonnage
Gabions are filled with bulk rock containing voids, so tonnes per cubic metre are lower than the solid density of the mineral. The correct conversion uses the supplier's measured loose bulk density for the selected grading and moisture condition. As a planning example only, a bulk density might fall around 1.5 to 1.8 tonnes per cubic metre, but quarry data should replace assumptions. Multiply total basket volume by the confirmed bulk density to estimate tonnage. Do not use solid granite or limestone density directly; doing so can materially overstate the delivered mass.
Allow for Settlement, Waste and Sorting
Add a project allowance for spillage, breakage, unsuitable pieces, trimming, and settlement during placement. The percentage depends on quarry consistency, transport, handling, basket geometry, workmanship, and how much visible face stone is hand selected. Remote projects may need a larger contingency because replacement deliveries are expensive. Decorative walls often require separate quantities for selected facing stone and economical core fill. Structural work must still use fill that meets durability, grading, and mesh-retention requirements throughout; cheap fines or weak rock in the core can migrate or degrade.
Match Stone Size to Mesh and Unit Depth
The smallest stone dimension must not pass through the mesh under placement and service movement. At the same time, pieces must be small enough to pack without large voids, bridging, or excessive basket distortion. Thin mattresses normally require a tighter grading than deep baskets. Oversized boulders reduce placement quality and can damage coatings; too many small pieces escape or settle. State both mesh opening and stone grading in the procurement documents and confirm a representative sample when the quarry is unfamiliar. Water and frost exposure also require sound, durable rock rather than material that slakes or splits.
Separate Mesh Shipping from Local Stone Logistics
Exported gabions are normally shipped flat-packed, while stone is sourced near the project because transporting rock internationally is rarely economical. Plan the two supply chains separately: basket production and container delivery from Zhongman, then quarry approval, haul routes, stockpiles, loaders, and placement equipment locally. Schedule enough stone ahead of each work front without blocking assembly areas. For prefilled or liftable units, filled mass, staging space, crane capacity, and transport restraints become part of the calculation. Container plans should be based on flat-pack mesh volume and weight, not the future filled volume.
RFQ Checklist
Send Zhongman a basket and mattress schedule with dimensions, quantities, mesh, wire, coating, accessories, and delivery sequence. For stone coordination, include the proposed grading and bulk density so mesh compatibility and estimated fill can be checked. We can quote the manufactured gabion package and provide a clear packing list; the local contractor should confirm quarry quantities through trial filling and measured bulk density before final stone purchase.