Geotube® Sand Filled Mattress Revetment Structure for Artificial Waterway at Clark International Airport Terminal 2

The Challenge

The Clark International Airport located within the Clark Freeport Zone makes headway in the aviation industry with its modern passenger terminals. It serves as a gateway to the north and as an alternative to the main airport in Metro Manila.

Part of the project is to create an artificial waterway which will serve as a catch basin for water run-off within the airport. Lahar, the slurry of thick debris, is abundant in the area and is a major concern for the erosion of the waterway being made. A revetment structure is thus required for the erosion protection of the new waterway.

The Design

TenCate Geotube® Sand Filled Mattress was proposed as the ideal solution for the waterway section for its slope erosion protection capabilities offering excellence in robustness, abrasion resistance and durability. A special substrate integrated to the upper surface of the sand filled mattress provides a surface texture that encourages the rapid establishment of vegetation for a long term vegetation cover to be in place.

The Construction

Prior to laying, a layer of Polyfelt® TS 60 non woven geotextile was installed on the slope for separation and scouring of the slope during hydraulic filling of the sand filled mattress.

The Geotube® Sand Filled Mattress, delivered in rolls, were laid with parallel tubular sections running down a 1:1 slope. Each were hydraulically filled with sand through the top openings. The sand was introduced through a small hopper and washed down with water. Adjacent rolls of the sand filled mattresses were joined by seaming on site.

Finally, the sand filled mattresses were anchored in a trench at the top of the slope.

The Performance

TenCate Geotube® Sand Filled Mattress was used as revetment for the whole waterway network within the new Clark Airport Terminal.

The rolls were easy to transport while installation was quick and easy using simple equipment. Skilled labour was not necessary. It is an effective erosion protection solution for the long run given the high robustness and durability of the composite with significant abrasion and UV resistance. A revisit to the site showed natural vegetation had flourished significantly and covered the sand filled mattresses.

Photo credit to Bases Conversion and Development Authority.

Overview of the revetment installed with Geotube® Sand Filled Mattress

Laying of Polyfelt® TS60 nonwoven geotextiles to prepare the slopes

Geotube® Sand Filled Mattress laid and joined to adjacent mattresses by seaming on site

Geotube® Sand Filled Mattress covered with vegetation