ProtectaWeb Slope Stabilisation Installation Procedure
Preparation
- Start site preparation for the ProtectaWeb slope protection system by removing debris and vegetative cover from the embankment area.
- Complete other earthworks, excavation and/or fills.
- Remove unacceptable in-situ soils that are for the ProtectaWeb slope protection system and replace with suitable materials.
- Excavate the specified toe-in trenches where specified along the crest and at the bottom of the embankment area being protected.
Embankment Protection and Drainage
- Install the Multitrack 1000 over the slope and secure in position according to the manufacturer’s recommendations. When excessive ground water is present, a nonwoven geotextile is recommended.
- Install the appropriate geocomposite drainage system (site specific). Ensure that the system is functional and connected to the suitable drainage outlet.
Installation of ProtectaWeb Slope Protection Sections
- Drive specified straight Pins part way into the ground along the toe-in trench or along the top of the area to be protected at the following longitudinal centres.
- Expand the ProtectaWeb section and place each expanded end cell of the section over its corresponding pre-installed stake. 3. Drive the stake Pins through the cells ensuring the hook loops over the cell wall.
- Expand the ProtectaWeb section down the slope to the fully expanded length of the section.
- Hold the fully expanded sections open using one of the following options. Other options are also acceptable:
- Straight stakes / pins (permanent or temporary)
- Infill several of the peripheral cells
- Check each ProtectaWeb section to ensure that it is fully expanded. Full expansion of sections will result in a better fitting and looking slope protection.
- Correctly align and interleaf edges of adjoining ProtectaWeb sections and ensure that the upper surface of adjoining sections are flush.
- Fasten ProtectaWeb sections together with staples or as specified in contract documents.
- Drive additional straight stakes or Pins at the specified spacing within the cells of the expanded ProtectaWeb.
- If the slope length is longer than one expanded ProtectaWeb section, drive another row of stakes at the bottom end of the expanded section per item 1 above and continue with the new ProtectaWeb section per item 2.
Placement of infill in ProtectaWeb sections
- After ProtectaWeb sections have been secured to the slope, begin infilling with the specified materials.
- Place infill in expanded cells with suitable material handling equipment.
- Limit drop height of infill material to 1 m maximum.
- Avoid displacement of ProtectaWeb sections by infilling from the embankment crest to the toe.
- Overfill ProtectaWeb sections and compact infill material as follows:
- Screened top soil, overfill between 25 mm and 50 mm and lightly tamp to leave soil flush with top edge of cell walls. Apply specified surface treatment.
- Loose granular materials, overfill 25 mm and compact with a plate tamper or machine bucket. Remove loose surface material so infill is flush with top edges of cell walls.
- Concrete, fill to top edges of the cell walls and compact manually or with vibratory equipment. Apply specified finish to concrete infill
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