When building embankments on weak soils such as clay, peat or silt there occurs a problem of insufficient bearing capacity and susceptibility to deformation. To solve the problem, geosynthetics such as woven geotextile are used. This material can considerably improve the embankment soundness and durability by reinforcement and stabilization. This article considers two woven geotextile types i.e. polypropylene and polyester types.
Contents
Woven geotextile made of polypropylene
Woven geotextile made of polyester
Woven geotextile use in embankment construction
The benefits of using geotextile
Woven geotextile made of polypropylene
Woven geotextile made of polypropylene is a material manufactured by polypropylene yarn bonding. Polypropylene is characterized by high strength and resistance to aggressive chemicals that makes its use ideal for weak-base cases.
Functions and benefits:
- Weak soil reinforcement. Polypropylene geotextile ensures a uniform load distribution by reduction of local strains and the risk of embankment settlement and deformation.
- Layer separation. The material prevents inter-mixing of soil and embankment layers thus maintaining the structure integrity and increasing its durability.
Polyester woven geotextile
Polyester woven geotextile is made by bonding of polyester fibers. Polyester possesses high tensile strength and minimal deformability that makes it adequate for use in conditions requiring added strength and resistance to mechanical loads.
Functions and benefits:
- High tensile strength. Polyester fibers provide the material with tensile resistance to allow its use under high dynamic load conditions such as motorway and railway embankment foundations.
- Low elongation. Thanks to low elongation of polyester geotextile, the material retains its armoring properties even under a considerable load thus preventing the embankment deformation.
- Chemical resistance. Polyester is resistant to aggressive chemicals thus extending the material service life under contaminated or aggressive soil conditions.
Geospan PET woven geotextile is an example of such a material used in road construction and construction of weak-based foundations.
Woven geotextile use in embankment construction
Woven geotextile use in embankment reinforcement contains several key stages:
- Base preparation. Surface levelling and removal of vegetation or unstable soil layers.
- Geotextile laying. Woven geotextile is laid on the base prepared. It is important to avoid stretching and folds.
- Aggregate filling. Macadam, sand or gravel are filled on top of geotextile and compacted to increase the embankment bearing capacity.
- Layer-by-layer compacting. The embankments are compacted layer by layer to allow the structure maximal stability.
The benefits of woven geotextile use
Woven geotextile use provides a number of benefits. The main of them are:
- High strength at low elongation reduces the risk of settlement and deformation on weak soils.
- Resistance to aggressive agents makes the material adequate for use under contaminated or chemically aggressive soil conditions.
- Durability of up to 50 years ensures the structure long-term operation without the armoring layer replacement.
The materials such as Geospan GT PP and Geospan PET have proven their effectiveness by practice, ensuring reliable embankment reinforcement and increasing the structure durability.
Conclusions
Weak-based embankment reinforcement with woven geotextiles made of polypropylene and polyester used allows considerable improvement of the engineering facility performance. Thanks to their armoring properties, these materials provide a structure with reliability and durability. The usage of such materials as Geospan GT PP and Geospan PET provides an effective solution to the problem of weak soil reinforcement and considerably enhances the embankment stability under complicated conditions.
