Case Study: Strengthening Infrastructure for the Reliance Bio-Energy Project with Ocean Biaxial Geogrid 30 kN

Project overview

For the Reliance Bio-Energy Project, Ocean Non Wovens supplied 29,000 square metres of Ocean Biaxial Geogrid 30 kN and supported its installation under access roads, working platforms and foundation bases. The exact project location is not disclosed, for confidentiality reasons related to project operations and client agreements.

A bio-energy plant generates constant heavy traffic: feedstock trucks, process equipment and construction plant. The roads and platforms that carry it need stable, reinforced ground that resists rutting and long-term settlement. Ocean Non Wovens was engaged as the geosynthetics manufacturer and supplier for that reinforcement layer.

The ground engineering problem

Bio-energy facilities are often built on expansive or reclaimed land, where:

• Subgrade soils have moderate to low bearing capacity
• Repeated heavy axle loads cause rutting
• Seasonal moisture changes cause shrink–swell movement
• Differential settlement threatens pavement integrity
• Surface failures push maintenance costs up quickly

IRC:SP:59, the Indian Roads Congress guideline on geosynthetics in road pavements, covers the use of geogrids for base reinforcement and subgrade stabilisation in conditions like these.

How a biaxial geogrid works

When aggregate is compacted onto a geogrid, the stones lock into the apertures. The grid then holds the aggregate laterally, so it cannot spread sideways under a wheel load. The confined layer is stiffer and spreads the load over a wider area of subgrade, which reduces rutting and can allow a thinner granular layer for the same performance. A biaxial grid has similar strength in both directions, which suits roads and platforms where loads come from all directions.

Product used: Ocean Biaxial Geogrid 30 kN

• Tensile strength: 30 kN/m in both machine and cross directions
• Junction efficiency: > 90%, for load transfer through the nodes
• Aperture sized for aggregate interlock
• Made from polypropylene
• Resistant to acids, alkalis and biological attack
• UV stabilised for exposure during construction

Ocean’s published data for its 30 kN PP biaxial grades (tested to ASTM D6637 / EN ISO 10319) lists 10 kN/m at 2% strain and 20 kN/m at 5% strain in each direction. These low-strain values matter more than the ultimate strength, because a road base works at small strains.

Biaxial geogrids are used mainly for base course reinforcement, subgrade stabilisation, working platforms, and settlement control and load spreading, which matched the roads and service platforms on this project.

Scope of supply

Ocean Non Wovens delivered 29,000 SQM of Ocean Biaxial Geogrid 30 kN. The grid was laid beneath the granular layers that form the main load-bearing layer for internal roads, equipment circulation paths and foundation preparation zones, stabilising weak soil and reinforcing the pavement against repeated dynamic loads.

Installation

Step 1: Subgrade preparation

Loose material was removed and the subgrade compacted to a uniform bearing capacity. Depressions were corrected to avoid local stress points.

Step 2: Geogrid placement

Rolls were laid directly on the prepared surface with overlaps of 300–450 mm. This is the range FHWA guidance (FHWA-NHI-07-092) gives for subgrades with a CBR above 3; softer ground needs wider overlaps.

Step 3: Aggregate placement

Granular material of the specified thickness was placed over the grid. Vehicles were kept off the exposed geogrid to prevent displacement or damage.

Step 4: Compaction

Compaction locked the aggregate into the apertures and formed a stabilised composite layer.

Benefits observed

Engineering observations and post-installation reviews on the project reported:

1. Better load distribution: axle loads spread over a wider area of soil, reducing stress concentrations and rutting.
2. Less aggregate: reinforcement allowed an optimised layer thickness.
3. Construction efficiency: stabilised platforms let heavy machinery keep moving through monsoon weather windows.
4. Durability: reinforced pavements generally need less frequent maintenance.
5. Lower environmental load: less quarried aggregate means less extraction and haulage.

What decides field performance

Tensile strength is only part of the picture. On site, these factors matter as much:

1. Subgrade preparation. A geogrid cannot compensate for a poorly prepared subgrade. Uneven or under-compacted layers reduce its effect, whatever its rating.
2. Aggregate grading. Interlock depends on angular aggregate sized to suit the aperture.
3. Overlap and alignment. Short overlaps or misalignment on curves create gaps in the reinforcement.
4. Trafficking on bare grid. Driving on an uncovered geogrid damages junctions and displaces the grid, a common error when schedules are tight.
5. Whole-life cost. The extra cost of the grid is usually recovered through less aggregate, fewer rebuilds and less maintenance downtime.

Results summary

Across 29,000 SQM, the Ocean Biaxial Geogrid 30 kN gave the project higher bearing capacity over weak soils, lower rutting and settlement risk, lower aggregate use and faster construction progress.

About Ocean Non Wovens

Ocean Non Wovens manufactures geosynthetics and supports projects from site assessment and product recommendation through supply and soil reinforcement installation support. For infrastructure or renewable energy projects that need ground stabilisation, contact the team or browse more case studies.