In the sphere of geosynthetics and ground stabilization, the deployment of geogrids has grown significantly, serving functions in soil reinforcement, slope stabilization, retaining walls, and the base construction of roads and highways. There are many options available, two of the most popular being Fiberglass and Polyester. This article hopes to put head to head these two products, and clarify use of these products in construction, when one or another is the better choice.
Fiberglass Geogrid
Fiberglass Geogrids’ main construction material of fiberglass combines high tensile strength with durability, and is coated with PVC or Bitumen both of which are more moisture resistant than plastic, allowing less emitted chemical absorption. General uses for this type of Geogrid are their use in road construction, reinforcements in embankments and slopes, and other uses where loading is encountered, especially with high stress. See below a brief description of characteristics…1. High Tensile – Geogrids made with fiberglass sometimes strip at highway and rail grade crossings, and this also allows their use industrially with heavy traffic loads.2. Low Creep – Fiberglass Geogrids “relax” little with long term load, permitting there to be a consistent weight bearing overall.3. Chemical and UV – Fiberglass in general has excellent resistance to environment. That surface treatment prolongs life of the material.
Polyester GeogridsDimensional Stability – Fiberglass naturally has a lower tendency for dimensional changes under stress than polymer or plastic, thus doing a better overall job of retaining road subgrade and alignment in retaining walls. Polyester Geogrid
Polyester Geogrids (PET) are manufactured from high-tenacity polyester (PET) yarns that may be woven together in a grid to be mechanically bonded, or knitted. Also coated with PVC and other polymers for added protection against overwrinkling from thermal expansion, at the same time increasing resistance to physical/external factors. Best suited for soft soil stabilization and embankment reinforcement where flexibility and elongation is important.
Key Characteristics
- Moderate Flexibility with High Strength – A great balance between the two makes it the perfect candidate for soft soil stabilization and embankment reinforcement.
- Fairly Good Creep Resistance – PET fibers can and maintain its strength over a long time when put under constant repeated pressure.
- Fairly good Durability – The polymer coating here protects against moisture, chemical and UV exposure similar to fiberglass geogrids.
- Rather Easy to Handle – Also lighter and more flexible than fiberglass, therefore it can be fairly easy to install on steep slopes also, on irregular faces are equally terrain. Comparing Performance: Fiberglass vs Polyester
When it comes to geogrid choice it should be based on your application. Heavy loads, soil choices, requirements, environmental issues and the like.Consider below a face-to-face comparison on a performance basis.
Polyester with Geogrid:
Polyester Geogrids (with a Geogrid span) versus Fibreglass.
Polyester Geogrids. Made from polyester fibres and possess lower levels of tensile strength than Fibreglass; however, they have more than enough load capacity for use in the soft soil stabilisation of slopes, and for reinforced embankments etc. Creep and Long Term Stability: The elongation of the material over time under a constant load is termed creep. Fibreglass geogrid products have very low degrees of creep, thus assuring its long term (several decades) dimensional stability. Polyester geogrids also perform well here, but in cases of indented sustained loads, the Fibreglass tends to keep its shape a little better over periods extended out over decades.
Environmental Resistance: Both are coated geogrids to make them resistant to moisture, and the deletereous effect of further exposure to ultra violet light and other chemical. However, Fibreglass has a better natural ready resistance to chemical attack and temperature fluctuation making it suitable for aggressive environments involving high alkalinity type soils etc, thus giving it a lower life cycle cost,. The cheaper lighter weight Polyester Geogrids ti isior not used as an alternative.
Installation and Handling: Its lighter weight means thate both of these geosynthetic products are that much less of a “hazard” being both carried / transported and so laid at the work site, though the polyester Geogrid is also a little more “friendly” on the steep slopes or rougher arrangements of ground topography etc as well where its flexible properties enables easier follow of lay-down on site thus reducing installation time and preventing excess effort.Fibreglass geogrids are stiffer and take more care to position correctly so that it lies flat and is properly tensioned. Cost issues: Cost is always a prime issue in deciding on materials. Fibreglass geogrids inevitably cost more whether because of the cost of raw materials or manufacturing, while Geogrids using the lighter and less expensive polyester are more economical for most uses (Earth Reinforcement, etc) and tend to stall an implementation costs on the good side of the line.
Where Fibreglass Geogrid is Used
Since it is perfect for applications which involve high stresses, there are quite a few places where this geogrid type will be found.
- Highway and Railway Reinforcement – As the name suggests, the properties of the material make it a soft glide for eliminating rutting and increasing the life of the pavement.
- Industrial Flooring – The geogrid type outlined here helps smoothen the pathway in storage areas and for heavy machinery.
- Reinforcement for Retaining Walls. Anything that keeps the wall in place and minimizes the movement of the soil.
- Slope Stabilization. As we pointed out in its properties, and for all intents and purposes in those of this geogrid type.
Where Polyester Geogrid is Used
On its own, the polyester geogrid makes its way into: - Soft Soil Reinforcement. Because it is cheap, a simple and effective means of boosting the capacity of soft soils.
- Landfill and Embankment Stabilization. Fewer odds of movement and edges remain closed.
- Reinforced Soil Structures (RSS).Now for retaining walls and terraces for the most part of moderate load retaining.
- Road Sub-base Reinforcement. Would be ideally used in unpaved roads for instance with less bustling traffic.
Which Geogrid is Right for Your Project?
When making a determination on which is best for your Geogrid project keep the following in mind.
- Load Requirements – Load bearing type of project go with the geogrid with fiberglass in it, otherwise go with polyester.
- Soil Conditions – Polyesther wins in soft and compressible conditions. Fiberglass wins in dense soils that are more likely to apply pressure loads.
- Environmental Exposure –The more severe the site in terms of for example chemical exposure and ongoing extreme temperature and UVs, then fiberglass it is.
- Complexity of Installation – Many times you would find, the polyesther geogrid for instance, begins to make sense from an installation perspective when it comes to projects being offroad and generally punishing, and minimizing installation costs as opposed to the great number of other products.
- Budget –Polycesther geogrid is just easier on the wallet in applications that are not life threatening, and fibreglass geogrid improves things on structural installations.
Following the above guidelines ensure that you make the right geogrid choice.
Conclusion
Needless to say, each of the geogrids has its own when and best type of use. All the same, it must then be said, it is the fibreglass reins in the structural war as far as bearing a load over time, and with minimal deformation. Long haul chief adversaries have got to use them under chemical bonding and UV degrading conditions. Polyesther has got the best bang for the buck then in making that noise with easy installations on soft soils, no doubt the best choice for this application.