EROSION & SEDIMENT

Coir ECB, Landlok TRM, Pyramat HP-TRM, geocell, silt fence

• Coir Mat: Temporary 6 to 18 months
• Landlok TRM (Turf Reinforcement Mat): Permanent, locks soil in place
• Pyramat HP-TRM (High Performance TRM): Permanent, ideal for very steep slopes
• Geocell: Cellular containment system, holds soils in place
• Silt Fence: Sediment control fabrics

COIR MAT

Coir is a natural erosion control product made from coconut fibres designed for temporary (6 to 24 months) applications. The product is supported on both sides by a synthetic (photo-degradable) mesh.

Coir erosion control blanket protects exposed slopes from loss of topsoil. It also greatly enhances seed and water retention allowing for faster growth.

eeek! Coir is processed from ripe coconut husks retted in freshwater for at least six months. This results in an increased resistance to UV (ultraviolet) degradation and also increases the flexibility of processed fibre without causing deterioration.

Advantages:

• Moisture absorption: factor 9 times its dry weight (900%)
• Retains humidity in the soil and atmosphere
• Slows discharge of water
• Excellent at reducing soil erosion
• Resists temperature and wind extremes
• Promotes and protects healthy growth of vegetation
• Biodegrades within time scale

Applications:

• Over steepened slopes, road, rail embankments, industrial, mining restoration, earth dams
• Drainage channels, culvert outlets, washout drains and emergency water courses
• Highly erodable soils (embankments and sandy / silty soil areas, high gradient slopes)
• Badly compacted areas, junctions with civil engineering works such as bridge abutments and inaccessible areas
• Unpredictable or low rainfall areas
• Heavy rainfall areas
• Irrigated areas
• Channels, coastal and sea shores - shore protection Public and private parks, terraces, dams
• Golf courses
• Lawns - temporary reinforcement and protection
• Roads - temporary reinforcement

LANDLOK TRM

Landlok TRM (Turf Reinforcement Mat) is a range of permanent erosion control products.

• Landlok 1051: X3 fibre polypropylene, net (topside) and geotextile (underside)
• Landlok 450: X3 fibre polypropylene, 2 nets (topside, underside)
• Landlok 300: Woven X3 fibre polypropylene

1st Generation (Landlok 450, Landlok 1051) Features and Benefits:

Provides permanent turf reinforcement to enhance vegetations natural ability to filter soil particles and prevent soil loss during storm events Utilises X3 fibre technology for up to 40% greater surface area to protect emerging seedlings and sediment retention 100% synthetic and UV stabilised

2nd Generation (Landlok 300) Features and Benefits. All of the above, plus:

A unique patented matrix of pyramids formed with X3 fibres that gridlocks soil in place under high flow rates Greater flexibility to maintain intimate contact with subgrade, resulting in fast seedling emergence and minimal soil loss.

Main Properties of Landlok TRMs:

• Tensile strength: high strength and low strain minimises seed, root damage and material under heavy loads
• Flexibility: greater flexibility allows Landlok TRMs to conform and maintain intimate contact with the prepared grade, ensuring the success of installation
• UV resistance: all Landlok TRM components are constructed with the top tested UV stabilisers such as carbon black and hindered amine light stabilisers

PYRAMAT HP-TRM

Pyramat HP-TRM (High Performance Turf Reinforcement Mat) is the most sophisticated vegetation enhancing mat on earth! Exceptional UV resistance.

Pyramat is a high performance 3-dimensional permanent TRM (Turf Reinforcement Mat).

• 10 times stronger than traditional TRM's
• Ideal for extremely steep slopes
• Has 3 times the UV resistance of a conventional TRM

Description:

Pyramat is a high performance 3-dimensional mat manufactured in the USA. The strength of Pyramat is due to its patented and unique woven geotextile construction. The method gives Pyramat unsurpassed dimensional stability, functional longevity which is not found in other types of permanent or degradable erosion control products. Its UV stability makes it ideal for arid and semi arid environments where total vegetation cover is not likely to occur. Pyramat's ability to resist higher water velocities and shear stresses due to its strength and ability to hold soil and vegetation combine to stabilise the slope faster.

Available colours: Green, Tan.

Main Features of Pyramat HP-TRMs:

• Construction: Patented 3-dimensional woven matrix makes it 10 times stronger than first generation TRMs, with performance unequalled in turf reinforcement.
• Tensile Strength: 1800 kg/m (58.4 kN/m) tensile strength meets U.S. EPA definition of a High Performance Turf Reinforcement Mat.
• UV Resistance: Patented UV protection package provides superior resistance to the damaging effects of ultraviolet radiation.

Outperforms and is more cost-effective than conventional erosion control methods, including:

• Large rock riprap
• Grouted riprap
• Gabions
• Concrete paving
• Hard roadside shoulders
• Articulated concrete blocks
• Fabric formed revetments

GEOCELL

Geocell is an effective cellular confinement system providing a cost-effective solution for ground stabilisation, erosion control and earth retention on slopes.

An innovative geosynthetic product Geocell is a lightweight and flexible cellular structure made from connected polyethylene strips. By ultrasonically bonding the strips together an extremely strong and flexible configuration is produced.

A variety infill materials can be filled into the geocell system; aggregate, concrete, sand, soil, etc.

Applications:

The variety of infill materials provides a versatile and economical geosynthetic solution for many applications including:

• Slope Protection: Prevents sliding by providing sufficient weight at the foot and along the face of the slope.
• Earth Protection: Prevents erosion actions of wind and water on exposed soils.
• Channel Protection: Protects channel slopes from soil erosion and confines the infill materials of channel bed and banks.

Textured or Smooth:

The decision to use Smooth or Textured is up to the customer. The main benefit from using Textured over Smooth is the higher degree of frictional interaction between the infill material and the geocell wall. This results in increases of the stiffness of the system by reducing the ability of a shear plane developing between the infill and the cell wall. With larger aggregate this difference is negated.

Slope Protection Applications:

Most slope protection applications utilize 10 cm (4 in) depth, standard cell sections. However, this is a function of (1) the potential minimum angle of repose (fiction angle) of the infill material, (2) the slope inclination, (3) the slope length of the individual cell, (4) the depth of the cell, and (5) the characteristics of the infill material.

Cell size is governed by slope geometry and design cover thickness.

Steep slopes must have global stability or be internally reinforced before application of the geocell system. The single-layer geocell system has been used on slopes as steep as 75 degrees. The controlling factors are the angle of repose (friction angle) of the infill material and slope inclination. Steep slope applications will require additional anchoring mechanisms such as polymeric tendons with the anchor system.

Anchor methods used to secure the geocell system to a slope include wood stakes, metal J-pins, and other earth / tension anchors. Stakes bear against the top of the cell wall or against tendons passing through the cell. Anchor array spacing is determined through static analysis methods.

A variety of polymeric tendons covering a range of tensile strengths are available to meet anchorage requirements when anchor stakes cannot be used for the following reasons (1) they become too numerous, (2) geomembrane liner cannot be punctured, or (3) rock is present in the embankment. Integral polymeric tendons are tied to restraint pins to transfer sliding forces to the tendons. The tendons are then attached to an anchoring system at the top of the slope. Spacing and quantity of tendons are determined through static analysis methods.

Generally sections are connected to prevent relative movement of sections during the infilling operation using rivets or heavy-duty metal staples applied with a pneumatic stapler. A variety of rivets/ staples are available to meet site environmental conditions.

Advantages of the Perforated Cells:

1. In load support applications, a high degree of frictional interaction is developed between the aggregate infill and the cell wall that directly increases the stiffness of the system by reducing the ability of a shear plane developing between the infill and the cell wall.
2. In all application areas, the perforations allow water to move from cell to cell reducing undesirable cell ponding and providing lateral drainage.
3. In vegetated slope and channel protection systems, roots can grow through the perforations increasing the stability of the vegetated cover when subjected to gravitational and hydrodynamic forces.

SILT FENCE

In order to ensure sedimentation control during construction and to comply with the Resource Management Act and the District Plan it is mandatory to prevent runoff and sediment discharging off site or into the stormwater system.

This is achieved in part by installing silt fence barriers around the perimeter of the earthworks. A silt fence needs to have an adequately high UV resistance for the term required, plus it must meet specific filtration properties.

Syntex silt fence is available in two styles depending upon the performance requirements of the project.

Silt Fence Type 1 (Woven):

A woven product manufactured with slit film yarns.

Identified by a distinctive single orange marker line which runs along the top and bottom of the roll, 150 mm from the edge.

Silt Fence Type 2 (monofilament):

A high flow rate high performance silt fence. It is an engineered premium grade manufactured monofilament to offer optimum tensile, flow and filtration characteristics.

Identified by distinctive twin orange marker lines which run along the top and bottom of the roll. These lines are 150 mm from the edge.

ACCESSORY

• Waratah Steel Stake
• Waratah Caps

Waratah:

Available single or per pallet. Waratahs are used to hold silt fence in place.

Waratah cap is a plastic cap (yellow) which fits over the top to protect people.