| Summary: |
The potential of replacing conventional coastal structural elements made of concrete units or rip-raps by geotextile containers in tailored dimensions is a topic at the forefront of Coastal Engineering research. With the improvements achieved at the level of the materials and the growing interest in the implementation of innovative techniques of coastal defense with lower environmental impacts, these measures are evolving towards becoming a real alternative to traditional solutions. The importance of these structures on shoreline protection is significant, due to their minimum environmental impact, cost-effectiveness, simplicity in placement and constructability, as well as reversibility if necessary. On the other hand, the growing interest on the application of these solutions is also related with the decreasing acceptance of the common shore protection measures, due to the high visual impact on the coast and the significant effects on the sediment transport by the littoral drift currents. Despite the important benefits the application of this protection system can bring, there is knowledge lacking, on the level of the design tools - practically inexistent - and on the level of their performance and stability on the long run, especially at more exposed hydraulic conditions. This project aims at researching the behavior and the stability of dune erosion control systems made with sand filled geocontainers when submitted to hydrodynamic loading of high energy. Particularly, aspects relating to the analysis of the wave reflection and transmission and to wave run-up and overtopping will be investigated. The influence of the deformation capacity of the structure and the properties of geosynthetics, namely permeability and elongation, will also be investigated. During the several phases of the project, different model types, varying namely the slope angle, the geocontainers material and the grain size of the fill material, will be investigated. Two kinds of waves - reg  |
Summary
The potential of replacing conventional coastal structural elements made of concrete units or rip-raps by geotextile containers in tailored dimensions is a topic at the forefront of Coastal Engineering research. With the improvements achieved at the level of the materials and the growing interest in the implementation of innovative techniques of coastal defense with lower environmental impacts, these measures are evolving towards becoming a real alternative to traditional solutions. The importance of these structures on shoreline protection is significant, due to their minimum environmental impact, cost-effectiveness, simplicity in placement and constructability, as well as reversibility if necessary. On the other hand, the growing interest on the application of these solutions is also related with the decreasing acceptance of the common shore protection measures, due to the high visual impact on the coast and the significant effects on the sediment transport by the littoral drift currents. Despite the important benefits the application of this protection system can bring, there is knowledge lacking, on the level of the design tools - practically inexistent - and on the level of their performance and stability on the long run, especially at more exposed hydraulic conditions. This project aims at researching the behavior and the stability of dune erosion control systems made with sand filled geocontainers when submitted to hydrodynamic loading of high energy. Particularly, aspects relating to the analysis of the wave reflection and transmission and to wave run-up and overtopping will be investigated. The influence of the deformation capacity of the structure and the properties of geosynthetics, namely permeability and elongation, will also be investigated. During the several phases of the project, different model types, varying namely the slope angle, the geocontainers material and the grain size of the fill material, will be investigated. Two kinds of waves - regular and random - will be also tested. For each type the structure stability will be studied for different wave heights and periods and water levels simulating different wave loading conditions that can occur along the Portuguese coast. The series of hydraulic model tests will be performed at two different scales in order to assess scale effects. This project will contribute to increase the knowledge on the performance and stability of this type of shoreline protection measures, for future practical application. Nevertheless, in face of the existing gaps, it will not cover all the research possibilities of research that can be pursued in following projects. |