GSC in Coastal Protection & Marine Construction
Ecocoast specializes in, among other things, coastal protection, and is a regional leader in providing soft and reversible solutions like Geosynthetic Sand Containers (GSC). These structures come in a wide spectra of varieties, which can be reflected in material specifications, shape and size of encapsulated sand and installation approach.
In the past few years, many new materials have emerged. This process is still ongoing, which ensures wider applicability of GSC in the future. Presently, many woven, non-woven and composite options are available in the market. Each of them have their own advantages and disadvantages. To give an example, on the one hand, very resistant and thick composite options can be used, designed to withstand heavy debris impact and vandalism with very limited UV-induced material fatigue, but, obviously at a higher price. On the other hand, less resistance and cheaper materials can be used at lower cost in some cases.
Ecocoast follows the world trends in this regard, and can offer its clients every possible option. Which one to use? Ecocoast’s technical team can advise you on this matter, and design the best solution for you.
The type of GSC depends on structure purpose (e.g. beach toe, revetment, breakwater) and environmental impact. There are 3 different options: bags (smaller units up to 5-6m3), tubes (much bigger and longer units), and containers (installed directly from split-hopper barges). Installation approaches are governed by site accessibility and many other variables, but it requires specialized personnel and equipment.
Final verdict in terms of cost-efficiency and feasibility is governed by many factors, but as these structures are, in a way, competing with the more traditional structures made of rocks - comparative pricing of those structures is a prevailing factor. That being said, fact that at some locations it is hard to use locally sourced rock while GSC enables use of rubble-like materials with no other value, can be significant. Also, one of the most important advantages of GSC structures is its removal. It is by rule, much cheaper, which makes them an attractive choice for temporary solutions.
Recently, Ecocoast has successfully installed these structures on a private island in Abu Dhabi. The changeable nature of the surrounding mobile sand shoals and migrating channels on the island required site-specific, low-risk and robust designs. The materials needed to be robust to effectively divert tidal flow, prevent erosion, protect the coastline and stabilize the island. A series of low crested, submerged sand-filled geocontainer breakwaters were installed, linked with a continuous toe to seaward combined with rock breakwater structures.
Aleksa Cavic - Technical Engineer at Ecocoast