Gabions ( boxes and Reno mattresses) shall be as manufactured by ISO certified manufacturer approved by the Engineer and shall be of the type and size indicated on the drawings and specifications.
The gabions in the boxes forms shall be made of P.V.C. coated (green) galvanised steel wire to BS 443, 2.70mm diameter with a nominal mesh size of 80mm x 100mm.
The mattresses form gabions shall be made of P.V.C. coated (green) galvanised steel wire, 2.20mm diameter with a nominal mesh size of 60mm x 80mm.
Stone filling to the gabions boxes shall be not larger than 300mm or smaller than 100mm, and to the mattresses not larger than 200mm or smaller than 75mm, with 5% of smaller material being allowable.
Stone fill for gabions shall consist of hard durable natural gravel or rock derived from a source approved by the Engineer, and complying with the durability tests for upstream slope protection.
Stone shall be evenly graded in accordance with the gradings shown on the drawings and Table.
|
|
Stone Fill Zone Size (mm) |
|
|
|
G1/G2 |
G3 |
|
Maximum |
300 |
200 |
|
Nominal D50 |
200 |
150 |
|
Minimum |
100 |
100 |
Gabion Infill Grading Limits
Assembly and erection of gabions boxes and mattresses shall be carried out in accordance with the specification and the manufacturer’s instructions and to the satisfaction of the Engineer.
Filling of Gabions and mattresses shall be by hand or by machine as necessary to ensure the stone is tightly packed to the satisfaction of the Engineer.
Quality Assurance techniques shall be used to control the manufacturing and installation procedures.