Geogrid is a tensile element introduced into soil which is weak in tension and cannot bear loads beyond its capacity, where in the geogrid enhances the soils capacity to bear loads

 Woven polyester geogrid consists of a regular network of connected tensile elements made of high-tensile polyester yarns with aperture geometry sufficient to permit significant mechanical interlock with the surrounding soil.  

The geogrid structure is dimensionally stable and able to retain its geometry under manufacture, transport, and installation.  The high-tensile polyester yarn provides relatively high tensile strength at low strains, high modulus and low-creep potential.  The apertures vary in size and provide an open area around 40 per cent.  The openings or holes in geogrids are rectangles in order to provide effective soil grid interaction. Geogrid is a tensile element introduced into soil which is weak in tension and cannot bear loads beyond its capacity, where in the geogrid enhances the soils capacity to bear loads.

Manufacturing techniques are utilised where polyester woven geogrid are constructed of high molecular weight and high tenacity polyester yarns utilising a complex weaving process using the best available weaving equipment in the world and optimum temperature PVC coating technology to provide superior engineering properties. Yarns are woven into a dimensionally stable, uniform network of apertures providing significant tensile reinforcement capacity. The geogrid is engineered to be mechanically and chemically durable, in both the harsh construction installation phase and in aggressive soil environments (pH range from 2 – 10). The PVC UV stabilised coating provides further chemical and mechanical benefits.

Woven polyester geogrid is broadly divided into two categories depending on the different tensile strengths along the two directions of the fabric as listed below. Both the polyester geogrids composed of high molecular weight, high tenacity multi-filament polyester yarns, and has a PVC coating which offers UV resistance and further strengthens the geogrid and minimises fibre degradation.

Uniaxial Geogrid
Uniaxial geogrid is manufactured with its tensile strength being higher in one direction so that it is used in applications where the major principal stress direction is known and the Geogrid is placed with its higher strength direction along the major principal stress direction. Some of the applications of Uniaxial geogrids are:
• Reinforcement and stabilisation of embankment and side slope
• Retaining wall.

Biaxial Geogrid
Biaxial geogrid has been manufactured with nominally equal tensile strength in two directions perpendicular to one another. Some of the applications of biaxial geogrids are:
• Roadbed reinforcement of road and railway, crack prevention, increase of roadbed strength
• Dyke reinforcement on soft ground for stress evenness, sedimentation adjustment, increase of stability and loading capacity of foundation
• Soft Soil reinforcement.

The features of geogrid include high tensile strength at low elongation, high long-term design strength and it has excellent creep resistance with flexibility and durability. It also has increased pull-out resistance with high chemical and biological resistance. The most attractive is that is cost-effective can be custom fabricated.

There are a few companies in the world who manufacture high-tensile woven polyester geogrid and CTM Geosynthetics is the pioneer company in India to manufacture woven polyester geogrids. It is a group company of CTM Technical Textiles Ltd., founded by Amit Agarwal, as a part of Chatarbhuj Lajpatrai Group Company. The company is manufacturing geogrids from new generation of high-tenacity polyester yarn. CTM Geosynthetics has been formed with a team of highly qualified and fully competent civil, geotechnical, transportation and environmental engineers to undertake the design and detailed engineering for a wide range of applications. The company is equipped with the latest 4th generation weaving machine and online PVC coating imported from Germany at its state of art manufacturing facility at Ahmedabad. Technically qualified manpower and internationally accepted design technology also intends through design and offer turnkey solutions in the areas like roads, railways, environmental and waste management solutions and costal and water front structures.

Authored by__

Amit Agarwal,
CEO, CTM Geosynthetics