Gabion Baskets and Geotextiles for River Training in Bridges Construction - Gabions PVC Coated and Galvanised Carbon Steel Wire Fabricated of Hexagonal Woven Wire Mesh

Basket gabions lined with geotextile fabrics are major structure for the construction of bridges along highways with the associated road approaches and earthworks.

How do Gabions and Geotextile Fabrics form a bank protection system suitable for carrying out bridge projects?

General Introduction:
As part of the bridge construction works, the Gabion Basket and Geotextiles are needed for the river training and bank protection.

Gabions and geotextile fabrics work together to form strong draining-free gabions wall river banks suitable for bridge construction. Construction of levees and platforms for river training works, and realignment of channels and reshaping of river channels adjacent to bridges shall be carried out. The bridge structures are generally founded on steel tube piles with cast in-situ substructures. The superstructures consist of steel plate girders capped with cast in-situ concrete decks. These structure along the river requires a good ground and surrounding soil condition to support.

The gabion baskets shall be flexible P.V.C. coated and galvanised wire boxes fabricated of hexagonal woven wire mesh. Each gabion shall be divided by diaphragms into cells and selvedged. All wire used in the fabrication of the gabions and in the wiring operations during construction shall, after galvanising, have extruded on to it a coating of polyvinyl chloride or “PVC.” The coating has an average thickness of 0.55 mm and nowhere be less than 0.40 mm in thickness. The pvc coated gabion mattresses are capable of resisting deleterious effects of natural weather exposure and immersion in salt water.

Geotextiles are permeable geo-synthetics made of synthetic fibers which is extremely difficult to tear or break. Geotextile fabric for gabions construction is a composite synthetic non-woven material bonded into a homogeneous sheet from a continuous filament and needle punched. The fabric is resistant to degradation caused by exposure to sunlight and it shall pass series standards including Breaking Load and Elongation of Geotextiles, Static Puncture Strength and Trapezoid Tearing Strength tests. Geotextile fabric shall be placed directly on the surfaces behind or under rip rap, stone beaching, retaining walls, drainage backfill,
gabions and mattresses and in any other locations which the project construction required.

Above combination of gabion mattress and geotextiles forms ideal protective riverbanks, platforms, channels adjacent to bridges.

River Training and Bank Protection in Bridge Construction Projects:

The river training gabions – geotextile works construction can be divided as the following steps:

Gabions and mattresses /baskets /boxes;
Fabrication of gabions work;
Construction of Levees, Platforms for River training;
Works and the Realignment of Channels;
Using Geotextile Fabric to form Rock Rip Rap and bank slopes;
Concrete Armouring (Precast Concrete Units)
Planting covering and protection.

Standards & Specifications of Gabions:
Gabion Basket, P. V. C. Powder Coated:
Size:
Gabion Basket - 2m by 1m by 0.5m
Gabion Basket - 1.5m by 1m by 0.5m
Quantity: According to work scope and projects details.
Uses: River Training and Bank Protection.
Works Specification Standard - River Training and Bank Protection.

Wires for Gabion Mesh

All tests on wire must be performed prior to manufacturing the gabion mesh.

1. Tensile strength: the wire used for the manufacture of gabions shall have a tensile strength between 350-500 MPa according to EN 10223-3. Wire tolerances (Table 3) are in accordance with EN10223-3. 

2. Elongation: Elongation shall not be less than 10%, in accordance with EN10223-3.

3. Zinc coating: minimum quantities of zinc shown at Table 3 meet the requirements of EN10244-2 Class A.

4. Adhesion of zinc: the adhesion of the zinc coating to the wire shall be such that, when the wire is wrapped six turns around a mandrel having four times the diameter of the wire, it does not flake or crack when rubbing it with the bare fingers, in accordance with ASTM A641-97.

We supply zinc coated galvanised carbon steel wire gabion basket meeting the standard following:

 ASTM-A-641 Class 3 - Standard Specification for Zinc Coated (Galvanised) Carbon Steel Wire;
ASTM-A-641M - Standard Specification for Zinc Coated (Galvanised) Carbon Steel Wire;
 ASTM D1242-56(75) - Standard Test Methods for Resistance of Plastic Materials to Abrasion;
 ASTM B 117-90 - Standard Test Method of Salt Spray (fog) Testing;
ASTM D1499-92 - Standard Practice for Filtered Open-Flame Carbon-Arc Exposures of Plastics;
ASTM G23(93) - Standard Practice for Operating Light-Exposure Apparatus (Carbon-Arc Type) With and Without Water for Exposure of Non-metallic Materials;
ASTM D1203-89 - Standard Test Methods for Volatile Loss From Plastics Using Activated Carbon Method.

All edges of the gabions, diaphragms and end-panels, except as stated in Sub-clause 18.1.7 of this Specification, shall be selvedged with a wire of which the core diameter is 3.4mm.

The gabions and mattresses shall not be placed until the bank has been trimmed and compacted.

Tolerances for Wire Diameter and Gabions Dimensions: A tolerance on the diameters of all wire of + 2½ per cent shall be permitted. The length of the gabions is subject to a tolerance of + 3 per
cent and the width of gabions to a tolerance of + 25 mm. All other gabion dimensions are subject to a tolerance of + 3 per cent of the sizes.

Learn more technical detailsincluding Gabion Wire, PVC Coating Requirements, Gabion Mesh, Selvage, Mesh Panel, Binding of Gabions and Tolerances of Gabion Sizes for Mattress and Boxes Suitable for Bridge Construction.

Geotextiles Fabric for Gabions Wall River Training Projects:
Specification:
1) Weight / Mass:100gsm - 1500gsm
2) Width:Within 9m  
3) length: 50-100m/roll (at request)
4) Material: PP / PET 
5) Color: Black,white,grey
6) Manufacturing method: nonwoven(short fiber needle punched) 
 
Aerct Geotextiles enjoy these Advantages:
1. High strength , good creep property , excellent erosion resistance, aging-resistance;
2. Good permeation, filtration , drainage, reinforcement, protection and maintenance function.

Made of vinyl chloride polymer, Geotextiles for Gabions Work Shall meet the following standards:
ASTM D2287-92 E2 - Standard Specification for Non rigid Vinyl Chloride Polymer and Copolymer Molding and Extrusion Compound;
ASTM D2124-62T - Standard Test Method for Analysis of Components in Poly (Vinyl Chloride) Compounds Using an Infrared Spectrophotometric Technique;
ASTM D4632 - Standard Test Method for Grab Breaking Load and Elongation of Geotextiles;
 ASTM D6241 - Standard Test Method for Static Puncture Strength of Geotextiles and Geotextile-Related Products Using a 50–mm Probe;
ASTM D4533 - Standard Test Method for Trapezoid Tearing Strength of Geotextiles;
ASTM D4355 - Standard Test Method for Deterioration of Geotextiles by Exposure to Light, Moisture and Heat in a Xenon Arc Type Apparatus;
ASTM D4491 Standard Test Methods for Water Permeability of Geotextiles by Permittivity;
ASTM D4751 Standard Test Method for Determining Apparent Opening Size of a Geotextile.

Geotextile fabric is placed directly on the surfaces behind or under rip rap, stone beaching, retaining walls, drainage backfill, gabions and Reno mattresses. The fabric shall be joined by overlapping with a minimum overlap of 300 mm above water level and 900 mm below water level. Geotextile fabric plays an important role in forming of rock rip rap and slope protection works.

Construction of Levees, Platforms for River Training Works and Channels with Gabions Cells:

Levees and platforms for river bank protection works shall be constructed with fabrication of gabions cells. Realignment of channels and reshaping of river channels adjacent to bridges are carried out also by gabions works. Learn details.

Forming of Rock Rip and Slopes with Gabions and Geotextiles:
Geotextile fabric is placed directly on the surfaces behind or under rip rap, stone beaching, retaining walls, drainage backfill, gabions and Reno mattresses. The fabric shall be joined by overlapping with a minimum overlap of 300 mm above water level and 900 mm below water level.
Geotextile fabric plays an important role in forming of rock rip rap and slope protection works. Learn more about data sheet, installation of geotextile fabric and forming of rock rip rap and slopes with geotextile filter cloth.

Concrete Armouring of River Slopes and Base for the Bridge Construction:

Precast concrete armouring units shall be placed for slopes and base.

Slopes shall be prepared before precast concrete units shall be carefully placed.

Rock Rip Rap and Concrete Armouring shall include for all work including supply and placement of materials, collection transportation and placement of rip rap and other filling, excavation, filling compaction and trimming necessary to
construct the rock rip rap and concrete armouring to the lines and
levels specified for the project.

Measurement of the quantity of rock rip rap shall be in cubic metres
supplied and placed. Measurement of the quantity of concrete armouring shall be the
number of units supplied and placed.

How We will Pack and Deliver Gabions and Geotextile Fabrics to Customers:
We follow International Transport Packaging criteria:
1.     The equipment/materials shall be packaged to fit into in standard ISO Freight Containers for Full Container Loads (FCL).
2.     Equipment/materials shall be packaged to be within the legal limits of the transport vehicles used in the countries through which the package will be transported.
3.     Prior to shipment the goods shall be packaged in such a manner to ensure that during shipment and storage the goods will be protected from handling, weather, or any normal hazard. The goods shall be clearly identified, be securely bolted, strapped or otherwise fastened to prevent any relative movement.
4.     The following detailed list of shipping documents (originals) are provided:
 i.Shipping Manifests and Packing Lists;
 ii.Technical Documents;
 iii.Material Test Certificates;
iv.Certificate of Compliance (or Quality);
v.Commercial Invoice;
 vi.Fumigation Certificate (ISPM 15) (if applicable packaging is used);
vii.Packing declaration;
viii. Shippers Letter of Instruction (SLI);
 ix.Certificate of Origin (if required); and
 x.Harmonised System (HS) classification maybe supplied on request.