50mm Commercial Grids

IBRAN-O50 is the deepest grid in the range, specified where the loading is not the occasional delivery van but a working surface: HGV yards, plant compounds, agricultural traffic and access routes that carry the same axles every day.

Depth does a specific job. A deeper cell holds a taller column of aggregate, and a taller column distributes a concentrated axle load over a wider area of sub-base before it reaches the subgrade. On light duty that is unnecessary; under repeated heavy loading it is the difference between a surface that holds its profile and one that gradually deforms into ruts.

Where it works best

• HGV and delivery yards. Repeated heavy axle loads over the same lines, which is the hardest duty any surface faces.
• Plant and machinery compounds. Tracked plant, telehandlers and the point loads from container corners and cradle legs.
• Agricultural access. Loaded trailers on soft ground, where the combination of weight and saturation defeats shallower systems.
• Emergency and fire appliance routes. Where a specified carrying capacity has to be demonstrated to building control.

Choosing between the three depths

All three carry 500 t/m2 as a static figure. What separates them is how they behave under repeated loading and how much aggregate sits above the sub-base.

• 30mm IBRAN-O for gravel driveways, paths and domestic use, where shallow excavation is an advantage.
• 40mm IBRAN-X for reinforced grass, where the root zone needs depth to establish under traffic.
• 50mm IBRAN-C for commercial and agricultural traffic, where the loading is sustained rather than occasional.

If you are between two depths, take the deeper one. The extra cost across a project is small next to lifting and relaying a surface that was under-specified.

Installation

Sub-base depth is what governs performance at this duty, not the grid. For HGV traffic allow 150mm of compacted MOT Type 1 over a woven geotextile, laid in layers of no more than 75mm and compacted individually. For tractors and loaded trailers, 200mm or more. Blind, screed level, push-fit the grids and fill with angular 20-40mm crushed stone.