Advertisement

Abstract: The Long Term Performance of Geocomposite Drainage Materials Used as Capillary Break Layers

  • Alain Hérault
  • Dave Woods
Conference paper
Part of the Sustainable Civil Infrastructures book series (SUCI)

Abstract

In arid regions, groundwater is often saline and the water table can be relatively close to the surface. Capillary rise above the water table brings dissolved salts near to the surface of the ground which can result in severe problems for both vegetation and the foundations of building structures.

For vegetation to survive, it is essential that there is a barrier between the saline ground and the clean ground and that this barrier also provides good drainage. A capillary break layer is installed above the highest level of the water table so that the void is never totally saturated by ground water and that the capillary break has high in-plane flow capacity to remove excess precipitation and irrigation water that enters through the clean ground above.

Chloride ions within saline moisture can be drawn into stone and concrete where the resultant chemical reaction causes expansion and weakening of foundations and the degradation of architectural finishes such as marble flooring. An effective barrier is to provide a capillary break layer between saline ground and clean ground. The capillary break layer creates a void across which capillary rise of saline moisture is prevented.

In both instances it has become common to use geosynthetic drainage layers to provide this capillary break. This paper introduces the application of capillary break layers and discusses in detail the need for ample understanding of the in situ and long term performance characteristics of the different types of drainage composite.

References

  1. AFNOR 2017. NF G38-061 Use of geotextiles and geotextiles related products - drainage and filtration systems - justification of dimensioning and design elementsGoogle Scholar
  2. Böttcher, R.D.: Long-term flow capacity of geocomposites. In: Proceedings of 8th International Conference on Geosynthetics, Yokohama, Japan, pp. 423–426 (2006)Google Scholar
  3. Comité Français des Géosynthétiques: Recommandations pour l’emploi des Géosynthétiques dans les systèmes de Drainage et de Filtration (2014)Google Scholar
  4. Rawes, B., Holtus, R.: Salt Barrier Applications in the Middle East (2015)Google Scholar
  5. Stoltz, G., Hérault, A.: Long term filter intrusion phenomenon in several types of drainage structures. In: Euro-geo 6, Ljubljana, Slovenia, pp. 575–583 (2016)Google Scholar
  6. Touze Foltz, N., Hérault, A., Stoltz, G.: Evaluation of the decrease in long term water flow capacity of geo-composites due to filter intrusion. In: 7th International Congress on Environmental Geotechnics, Melbourne, pp. 321–329 (2014)Google Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Low & BonarParisFrance
  2. 2.Low & BonarLondonUK

Personalised recommendations