The ECOPODE™ unit
The ECOPODE™ is a single-layer armour unit that blends harmoniously into its surroundings, and can be used to build an eco-designed structure that encourages biodiversity. This unit has been designed with the same robustness and high hydraulic stability as the first-generation ACCROPODE™ while also, as far back as 1996, integrating aesthetic and environmental considerations.
This is a unit that can be adapted in line with the local environment in order to blend into its surroundings. Unlike the other units in the range carried by CLI, the characteristics of this unit can be adapted in line with the Project Owner’s requirements. In particular, a wide range of scalable mould fabrication technologies are available.
As a result, it takes a certain length of time to implement these scalable technologies and the Engineer must allow sufficient time for this process in his schedule. The theoretical maximum size of this unit is 10m3. As is the case with all CLI armour units, the ECOPODE™ has a high stability coefficient derived from its shape as well as from the associated placing techniques.
It can be used on structures of all types from coastal defences in shallow water to large breakwaters designed to protect ports or nuclear power plants. Last but not least, this is a technology with minimal maintenance costs since these structures are normally intended to withstand the design wave without sustaining damage. This unit is compatible with the ACCROPODE™ II.
Key points: the specificity of the ECOPODE™ technology is that it is scalable and can be adapted to the client’s requirements. It is therefore essential to launch discussions with CLI as early as possible in the project design phase.
Practical aspects of ECOPODE™ units
1. A simple formwork principle based on:
- Two steel symmetrical half-shells. This economical formwork is made with fibreglass and a steel frame assembled for easy concrete casting through the top.
- Ease of use thanks to its wheels, which do away with the need for lifting equipment .
- A proven technique ensuring seamless stripping.
2. Concrete strength specifications that are simple and open to the continuous improvements being made to this technology.
The concrete used for ECOPODE™ units is a simple mass concrete of a type similar to that used for the other ACCROPODE™ units, with the possibility of colouring in the mass. The specifications for producing this concrete are brief, to leave the project players free to choose the concrete characteristics best suited to their project. Concrete types that encourage marine species colonisation can be used, provided that they are compatible.
As stated in the specifications, CLI has confirmed on the basis of experience that the following characteristic strength values give a safety factor that is sufficient for the construction phases and during the working life of the structure:
|ECOPODE™||Units ≤ 4 m³||5 m³≤ units ≤ 10 m³|
|Concrete class required||C25/30||C30/35|
|Tensile strength Fctm||2.5 Mpa||3.0 Mpa|
|Minimum strength for
form stripping Fck Cyl
|6 MPa||7 MPa|
|Minimum strength for
handling Fck Cyl
|15 MPa||20 MPa|
|Minimum strength for
placing Fck Cyl
|25 MPa||30 MPa|
3. Unit fabrication
ECOPODE™ units are fabricated in a similar manner to ACCROPODE™ II units, using traditional methods. However, particular attention must be paid to the moulds. With the traditional fabrication method, the following parameters are adopted:
- Minimum area required to fabricate one unit: 2H² (where H = ECOPODE™ unit height).
- Fabrication of one unit per day and per mould.
4. Storage and handling
- Forklifts can be used to transport the units. For some very large units, handling equipment such as cranes and slings will be required.
- Units can be stored on one or two levels depending on their size, on levelled ground with a sufficient bearing capacity.
- Minimum area required to store 10 units on one level: 7.1H² (where H = ECOPODE™ unit height).
5. Unit placing
The ECOPODE™ II unit benefits from the experience gained with the first-generation units, and the placing conditions are similar to those of the ACCROPODE™ II. This unit is placed on an underlayer similar to that of the ACCROPODE™ II. A placing grid defines the theoretical target positions in order to place the units easily; according to the feedback we have received, this ensures that this ensures that the packing density required by the technique is obtained.
Today, DGPS / GPS RTK-type positioning systems are systematically used. Unit keying is achieved easily thanks to the random orientation of the units. The unit placing speed is determined by the resources used, which must take the weather conditions at the site into account. The use of a hydraulic shovel and a special grab can double the standard output of a cable crane.
Placement rate (using cable cranes) – monthly average
|Unit sizes||Average placing time per unit|
|Small||4 to 6 mins|
|Medium||7 to 10 min|
Higher rates can be obtained using a “custom” method.
Using the ECOPODE™ technology in association with technical assistance geared to the construction site makes it possible to:
Control the cost of building a facing with a low visual impact.
Reduce environmental impacts and create or restore ecosystems more easily.
Control and reduce the volumes of materials required, especially concrete.
Minimise risks and construction times, enabling the structure to be put into service more quickly.
Significantly reduce the costs of inspecting and maintaining the structure throughout its working life.