The works were carried out by Anelixis Constructions for ELINOIL Hellenic Petroleum Company S.A., with consultation services provided by SILVER PALM SM Pte Ltd Greece and PERENDES TECHNOLOGIES

In July 2018, Concrete Canvas® GCCM * (CC) was used to line containment bunds at a petroleum tank farm in Agria, Volos, Greece. The original concrete at the containment bund of liquid fuel tanks had cracked due to bad weather conditions, resulting the need of using CC to increase their impermeability and to prevent the surface of slopes from weathering and surface slip. The overall project involoved the laying of Concrete Canvas in seven (7) containment bunds, as well as on verticals slopes & intermediate areas of the facility.

Traditional concrete combined with shotcrete was considered initially but the main disadvantage of this option was the possible damage and inevitable mess caused by the “rebound” which would add significant cost and risk, particular when installed next to sensitive infrastructures such as tank farm. In addition, this solution would have been more time consuming and would put the tank farm out of operation for an extended period of time, which was impossible.

The access to the area was poor so CC was the best choice as it can be installed with basic equipment and following completely the substrate profile it could overcome these challenges without conversions on the complex existing mechanical installations (e.g. piping network, tank interconnections, etc.).

As an alternative, the use of a geotextile was also proposed. A material particularly fragile to cope with the weathering erosion but also to cover the vertically rocky slopes. Therefore, the high resistance to UV degradation, the 50-year life-span, and the easy & fast installation offered by CC, has brought it as the ideal solution, providing a safe installation.

For the preparation of the installation of Concrete Canvas, all plants, rocks and debris were removed for the purpose of the appropriate soil preparation. The existing surfaces of tank’s floor were cleaned and quarry sand was applied to eliminate voids under the CC.

The CC was mounted onto a spreader beam and was hanged from a crane. 2 Wide rolls of CC5 were then unrolled from the top of the slopes, with the team ensuring an overlap of 100 mm between layers. The CC was cut in sizes to fit the varying height of the slope, ensuring there was no wastage

The product was initially secured by fixing to the concrete surfaces with “Hilti” nails (37x3.5 mm) with steel washer diameter of 23 mm to prevent pull through. Then, between concrete walls and the crest of vertical slopes 400 pieces of J - pegs (12x250 mm) were used to anchor the layers of CC to the ground with a 2m interval between them. The slope’s rocky surface was drilled and anchor bolts (14x200 mm) were inserted along to secure the material to the slope. All the overlaps were sealed with an adhesive sealant and jointed with 25mm screws at 200mm intervals using an auto- fed screwdriver prior to hydration.