Case Study: Enhancing Durability and Efficiency in a Food Plant Project with Ocean Non Woven Geotextile

Project overview

A food plant in Uluberia, Howrah, needed stable ground under its floors and equipment, good drainage, and protection against soil movement in a wet setting. Ocean Non Wovens supplied and implemented 450 sqm of Ocean Non Woven Geotextile 150 GSM beneath the foundation for soil stabilization, separation and drainage.

Uluberia sits on the west bank of the Hooghly, on the soft, fine-grained alluvium of the lower Gangetic plain. Groundwater is shallow and the monsoon is heavy, so subgrades here soften and move with seasonal moisture changes. Food plants add their own load: process water, washdown, heavy machinery and storage racking.

What the geotextile does under a plant floor

A non-woven geotextile is a permeable, needle-punched polypropylene or polyester fabric. Placed between the natural subgrade and the granular sub-base under a floor or foundation, it does three things:

• Separation: keeps soft subgrade soil from pumping up into the sub-base and the sub-base stone from punching down into the soil, so the sub-base keeps its thickness and strength.
• Filtration & Drainage: lets water pass while holding back fine particles that would otherwise migrate into and clog drainage layers.
• Soil Stabilization: by keeping the layers intact, it limits the shifting and settling that lead to uneven floors and cracking.

The load-spreading comes from the sub-base, which the geotextile keeps clean and intact; a 150 GSM non-woven is a separator and filter, not a reinforcement layer.

Why 150 GSM

• Enough strength for installation: under a building floor the fabric is loaded mainly during placement and compaction of the sub-base. A 150 GSM grade survives that on a prepared, stone-free subgrade.
• High permeability: water passes through freely while the soil structure is retained.
• Chemical & Biological Resistance: polypropylene does not rot and is unaffected by moisture, food waste leachate or microbial activity in the soil.
• Cost-Effective: a light grade keeps material cost low for a separation layer that needs no maintenance once buried.

Challenges on site

1. Soil instability and moisture: the soil tended to shift with moisture changes, which leads to uneven flooring and structural damage. The geotextile beneath the foundation reduced movement between soil layers.
2. Drainage: standing water under a food plant encourages microbial growth and contamination. The geotextile acted as a filter, letting water drain without carrying away soil particles that could clog the system.
3. Load-bearing capacity: heavy machinery and storage units stress the ground, and a contaminated sub-base settles unevenly and cracks the floor above. Keeping the sub-base clean preserves its ability to spread those loads.

Installation basics

For a separation layer of this kind, the subgrade is trimmed and cleared of sharp debris, the geotextile is unrolled flat with overlaps of typically 300 mm or more (more on very soft ground), and the sub-base is spread from the edge onto the fabric rather than tipped directly onto it. The fabric is covered promptly to limit UV exposure.

Results

The geotextile layer gives the plant a stable, well-drained base: less risk of floor cracking and uneven settlement, drainage that does not silt up, a drier foundation that supports food safety requirements, and fewer foundation-related disruptions to heavy machinery.

Geotextiles for industrial sites

Ocean Non Wovens manufactures and supplies non-woven geotextiles in a range of GSM grades for food plants, warehouses, processing facilities and other industrial floors and yards. Tell us your subgrade, sub-base and loading, and we will recommend a grade.