Design Guide Fibertex Geotextiles
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Design Guide Fibertex Geotextiles

Geotextiles Fibertex Geotextiles - are needlepunched nonwoven fabrics made from polypropylene. The drylaid needlepunch technology is based on a two step process. Firstly, polypropylene resin is extruded into bres. Secondly, the bres are carded and needlepunched. Finally, some types are added thermal treatment. Weights range from 100 g/m2 up to 1200 g/m2. Focus on the environment No chemical binders are used in Fibertex products or during the production process. Polypropylene is a polymer material and when incinerated it turns into carbon dioxide and water vapour, both completely harmless...

To prevent mixing of construction layers To increase bearing capacity by avoiding material loss into the subgrade To improve the compaction properties of the aggregate layer To provide long-term stability of foundation layers Separation is the basic use of geotextiles and is widely practised in road works and railway constructions. In the EN ISO standards the separation function is defined as ”The preventing from intermixing of adjacent dissimilar soils and/ or fill materials by the use of a geotextile”. Geotextile properties The tensile strength, puncture resistance and elongation...

Fig. 1. High elongation and dynamic perforation resistance prevent the geotextile from being damaged when rocks are dropped during installation. Fig. 2. High elongation and tensile strength prevent damage of the geotextile when aggregate is horizontally displaced as a result of wedge effects during vertical pressure. Fig. 3. High elongation and static puncture resistance allow the geotextile to stretch around the irregular construction surface. Fig. 4. High elongation and static puncture resistance prevent puncture when pressure from the fill material causes migration of fine soil into...

Separation Important mechanical properties of a separation geotextile: Tf: The requirements for these properties are influenced by the following properties of the supporting soil: Tensile strength at break of the geotextile [kN/m] (Minimum value) According to EN ISO 10319 Californian Bearing Ratio [%], Relative value for the plastic deformation properties of a soil. Elongation at break [%] (Minimum value) Static puncture resistance (CBR-test) [N] (Minimum value) When knowing one of these two parameters and the load that the construction is to endure, the minimum cover layer and strength...

Characteristic opening size [lm] According to EN ISO 12956 Coefficient of permeability normal to the plane [m/sec] (Minimum value) According to EN ISO 11058 The requirements for these hydraulic properties vary according to construction type, depending on the type of water flow it must endure. (railway constructions and other constructions where pump effects may occur) Dynamic water flow may be a result of a pump effect generated by dynamic loads (e.g. railway constructions). Dynamic water flow can also occur naturally, which is the case with wave action on coastal areas. The function of a...

To avoid migration of fine material into coarse material as a result of water flow in the soil particles subjected to hydrodynamic forces while allowing the passage of fluids into or across a geotextile”. To maintain the water flow in the soil with minimum pressure loss Geotextile properties To prevent migration of fine material as a result of pump effects from dynamic loads such as traffic Geotextiles are widely used for filtration in road works and railway constructions as well as coastal protection. The filtration function of a geotextile serves the same purpose as the separation...

Fig. 5. High elongation and static puncture resistance allow the geotextile to stretch around the irregular construction surface. Fig. 6. High elongation and dynamic perforation resistance prevent the geotextile from being damaged when rocks are dropped during installation. Fig. 7. The correct hydraulic properties of the geotextile ensure that soil fines are retained while maintaining the water flow. Fig. 8. High elongation allows the geotextile to follow the contours of the irregular construction surface. The required mechanical properties of a geotextile are based on the failure...

Filtration Stressed filtration systems Important mechanical properties of a stressed filtration geotextile: values are influenced by the size of the load and the following properties of the supporting soil: Tensile strength at break of the geotextile [kN/m] (Minimum value) Californian Bearing Ratio [%], Relative value for the plastic deformation properties of a soil. Elongation at break [%] (Minimum value) When knowing one of these two parameters and the load the construction is to endure, the minimum cover layer and mechanical properties of the geotextile can be read from table 2. Static...

To function correctly, the characteristic opening size of the geotextile has to match the soil conditions. If the characteristic opening size is too large the soil particles will pass through the geotextile, whereas if it is too small, the water flow will be insufficient. The important hydraulic parameters of the geotextile are: The lower of the two values from the upper limit is chosen. Characteristic opening size [lm] According to EN ISO 12956 Dynamic water flow Coefficient of permeability normal to the plane [m/sec] (Minimum value) According to EN ISO 11058 The water flow through the...

To ensure that water and/or other fluids are drained with minimum pressure loss a soil and a coarse-grained drainage layer, the function is filtration. To ensure an ongoing drainage Geotextile properties Geotextiles are widely used for drainage in earth and construction works. In the EN ISO standards the drainage function is defined as ”The collecting and transporting of precipitation, ground water and/or other fluids in the plane of the geotextile”. In other words, it is the ability of the geotextile to drain fluids on its own, meaning that it is not part of a drainage system, but is the...