Geosynthetics, also called geotextiles, are increasingly implemented in hydraulic engineering projects. These are often cheaper and more environmentally-friendly than traditional techniques. The geosynthetics should be applied carefully during the construction of civil engineering structures, as failing to do so may result in damages.
This course provides an overview of known and novel applications of geotextiles in hydraulic engineering. Additionally, new design rules and implementation guidelines are presented, specifically for geosynthetics under stone revetments on dikes and geotextiles in sandy elements of hydraulic constructions. The latter can be used as an alternative for quarry stones or basalt.
During this course you will practice independently the use of design guidelines as documented in several publications, particularly the new Guideline Geotextiles under stone revetments (Dutch: Richtlijn Geotextielen onder steenbekledingen).
During this course you will learn:
Intended for
People involved in the design and execution of hydraulic structures in which geosynthetics are applied (clients, project leaders, designers, contractors, supervisors).
Taal |
Dit programma wordt in het Engels gegeven. |
Introduction to geosynthetics in hydraulics
Geosynthetics are applied extensively in hydraulics. The most widely used application of geotextiles in hydraulics is as a filter under rockfill constructions. What does a traditional filter construction with fully granular material look like? Which advantages do geotextiles offer? How have geotextiles for filter constructions evolved over time? A large number of subjects and developments will be presented during the introduction. Important aspects are the permeability and permittivity of geotextiles. Furthermore, specific design aspects for geotextiles in stone and sandy elements are explored.
Geosynthetics under stone revetments
Design philosophy. Design guideline SBRCUR1795, simple + detailed method
A geotextile forms part of the filter construction of a dike, dam or other water barrier. The main function of the geotextile is to prevent flushing of ground particles. A design guideline has been formulated for these requirements. The theoretical background as well as practical methods for calculations following these guidelines will be introduced during the course. This concerns quantification of functional requirements such as soil density and pore size, water permeability and resistance, and robustness requirements such as minimal tensile strength and strain constraints. A special application highlighted during the course are fascine mattresses, which are faced with additional requirements such as energy absorption of falling rocks during immersion.
Quality control and implementation aspects
Quality control, transport, prefabrication and implementation of fascine mattresses, geotextile systems and textured mats.
CUR 115 concerns the application of geosynthetics in hydraulics. This publication addresses the quality check during the production of geosynthetics, authorized institutions and inspections to be performed on-site (contractor, management/supervision). Important focusses are (un)loading, storage and prefabrication of geosynthetics. Several working methods of installing geotextiles in and under water are made comprehensible, including specific aspects of placing fascine mattresses, the roll-out of geotextiles, covering using lynch systems, or submersion from a pontoon or ship. Protection of banks is not only possible with geotextile systems, but also using 3D textured mats, which allow integration with vegetation. Further attention is paid to several implementation aspects of erosion mats in order to obtain sustainable and erosion resistant banks with vegetation, or reinforced grass revetments on dikes.
Research on the effects of deposited stones on geotextiles
Geotextiles often experience their highest load during installation. An example are stones deposited on a geotextile. The impact of falling stones regularly leads to damages to the geotextile. The circumstances in which damages occur have been assessed experimentally, but no calculation model exists yet. Drop tests have been performed at Ghent University with stones varying in shape and different geotextiles. The results form a first step towards such a calculation model, which is currently being validated in field trials. This research project, the calculation model and the field tests form the contribution of this subject to the course.
Durability, lifespan and environmental aspects of geosynthetics
It is a requirement for geotextiles in hydraulic structures that the material retains its characteristic properties for the whole life duration. In this course subject, chemical mechanisms related to degradation are treated and techniques are introduced that prevent or restrict this breakdown process. This forms the basis for the method used to determine the lifespan of geosynthetics. Also, it will be taught how to test and verify these aspects for a chosen material. The composition of geosynthetics is designed such that they retain a long lifetime and that they can be removed for recycling when their operating life has ended. The environmental aspects regarding geosynthetics are listed and the preconditions are illustrated for responsible and sustainable use of geotextile in hydraulics.
Design and application of geotextile containers, tubes and bags
Many hydraulic constructions have been build using geotextile sandy elements. Many design and implementation aspects are described in CUR-publications 214 and 217. For example, a long bank construction has been built on a soil with a very low load bearing capacity in Amsterdam, and in Lake Ijssel a breakwater has been built using geotextile elements. Thanks to geotextile elements, it is possible to build a hydraulic construction with lower CO2 emissions compared to traditional build-up methods. Additionally, geotextiles enable environment-friendly building methods using naturally occurring granular materials. This module highlights how to derive system choices and how a design can be converted into an execution plan.
“Positive, variety in subjects, good balance between theory and practical implementation.”Sebastiaan Maan (BT Geoconsult)
“Well learned how to apply the new standard.”Maurice de Graaf (Rijkswaterstaat)
“Useful, especially because of the new CUR guideline.”Cursist van Gemeente Rotterdam, stadsontwikkeling
“Instructive and I can immediately apply it in my work.”Cursist Sweco Nederland BV
“Instructive, practically applicable, backgrounds clarifying.”Cursist van Movares Nederland BV