3.1.1 Eco-grid
material performance data should be reported in accordance with the
corresponding standard or type test report.
3.1.2 The technical
parameters and specifications of the ecological grid shall comply with the
relevant provisions of Appendix A of this regulation.
3.1.3 Eco-grid
materials may be selected from PVC coated or highly corrosion-resistant steel
wire and steel wire without PVC coating or high corrosion resistance. The
strength, ductility and corrosion resistance of the steel wire should meet the
requirements. The steel wire should be hot-dip galvanized steel wire,
aluminum-zinc mixed rare earth alloy coated steel wire, and the same homogenous
steel wire coated with PVC or high anti-corrosion treatment. The model
representation can be expressed as shown in Figure 3.1.3.
Figure 3.1.3 Schematic representation of the model
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1—Ecological grid products: G for the solidification cage, L for the green
shore cushion, and J for the reinforced solid shore cage;
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2—Steel wire classification code, which can be selected according to Table
3.1.3; 3—Mesh D+ mesh diameter (mm)×10;
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4—length×width×height (m); 5—this standard number
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Table 3.1.3 Steel wire classification code table
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Code
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Steel wire
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Z
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Hot galvanized steel wire
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T（5%）
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Zinc-5% aluminum-mixed rare earth alloy steel wire
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T（10%）
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Zinc-10% aluminum-mixed rare earth alloy steel wire
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PZ
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Hot-dip galvanized PVC steel丝
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PT（5%）
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Zinc-5% aluminum-mixed rare earth alloy coated PVC steel wire
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PT（10%）
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Zinc-10% aluminum-mixed rare earth alloy coated PVC steel wire
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3.1.4 Underwater, water level fluctuation areas, marine conditions, salt
spray areas, soils with high acidity and high alkalinity should be coated with
aluminum-zinc mixed rare earth alloy coated steel wire coated with
PVC.
3.2 steel wire
3.2.1 The wire diameter tolerance shall comply
with the relevant requirements of the current industry standard "General Purpose
Low Carbon Steel Wire" YB/T 5294. The test of tensile strength and elongation at
break of steel wire shall comply with the current Chinese standard “Standard
Test Method for Tensile Stress of Metallic Materials” GB/T 228. The tensile
strength of steel wire shall be 350MPa~500MPa, and the elongation at break shall
not be less than 12%. The torsion test shall be carried out in accordance with
the current Chinese standard "Metal Wire Torsion Test Method" GB/T
239.
3.2.2 The galvanizing test shall be carried out according to the
current Chinese standard “Test method for zinc layer quality of galvanized steel
wire” GB/T 2973; the high galvanized low carbon steel wire to low galvanizing
amount shall be in accordance with the current industry standard “steel
galvanized layer” The A1 grade wire standard in YB/T 5357 is implemented. The
content of coating in zinc-5% aluminum coated steel wire shall be tested
according to the current Chinese standard "Zinc-5% aluminum-mixed rare earth
alloy coated steel wire and steel strand" GB/T 20492; zinc-5% aluminum-mixed
rare earth alloy coating The weight of the steel wire to the low plating layer
shall be in accordance with the A grade steel wire standard in GB/T
20492.
3.2.3 When the coating weight meets the requirements, the coating
uniformity test shall be carried out according to the current Chinese standard
“Test method for zinc-plated steel wire zinc layer copper sulfate” GB/T
2972.
3.2.4 The adhesion test of the coating shall be carried out in
accordance with the current Chinese standard “Test method for wire-wound of
metal materials” GB/T 2976. The coating adhered to the steel wire shall not be
cracked.
3.2.5 The salt spray test of steel wire shall be carried out
according to the current Chinese standard “Artificial Atmosphere Corrosion Test
Salt Spray Test” GB/T 10125. The steel wire shall pass the test of salt spray
test of not less than 3000h, the quality change rate of steel wire, the
corrosion rate of steel wire and the composition of steel wire. The change rate
of mesh quality shall not exceed the value specified in Table 3.2.5; the PVC
steel wire shall pass the 2000h salt spray test, and the penetration depth of
the flat end depth, that is, the corrosion of the steel wire shall be less than
15mm.
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Table 3.2.5 Steel wire corrosion resistance index
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Wire classification
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Wire quality change rate to large value (%)
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Corrosion rate to large value (g/m2)
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Net quality change rate to large value (%)
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High galvanized low carbon steel wire
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2.1
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130
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2
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High galvanized low carbon steel wireZinc-5% aluminum-mixed rare
earth alloy coated steel wire
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1.9
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110
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1.7
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Zinc-10% aluminum-mixed rare earth alloy coated steel wire
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1.7
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80
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1.5
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High galvanized low carbon package PVC steel wire
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1.5
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35
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1.5
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Zinc-5% aluminum-mixed rare earth alloy coating PVC steel wire
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1.2
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30
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1.2
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Zinc-10% aluminum-mixed rare earth alloy coating PVC steel wire
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1
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25
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1
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3.3 PVC coating
3.3.1 The thickness of the PVC
film should be 0.4mm~0.6mm.
3.3.2 The density of PVC raw materials should
be 1.30kg/m3 to 1.35kg/m3.
3.3.3 PVC raw material should be a Shore D
hardness of 50 to 60.
3.3.4 PVC raw material should be brittle
temperature test "vulcanized rubber brittle temperature test methods" GB 1682
performs embrittlement temperature should not exceed -9 ℃.
3.3.5 The
tensile strength and elongation at break of PVC raw materials shall be tested in
accordance with the Determination of Tensile Properties of Plastics GB/T 1040.1,
the tensile strength shall not be less than 20.6 MPa, and the elongation at
break shall not be less than 180. %.
3.3.6 The elastic modulus of PVC raw
materials includes tensile modulus and flexural modulus. The test shall be
carried out according to JB/T 6544, Test Method for Tensile and Bending Elastic
Modulus of Plastics. The modulus of elasticity shall not be lower than 18.6
MPa.
3.3.7 PVC raw materials should wear resistance test "plastic sliding
friction wear test method" GB 3960 executed.
3.3.8 PVC raw materials and
properties of salt spray resistance and aging resistance should meet the "green
solid shore cages and Bin pad (metal coating steel wire or PVC coated metal
coated steel wire) Standard" ASTM A 975 requirements, salt spray exposure After
the UV exposure test, the PVC performance change requirements should be
controlled in the following range: density change does not exceed 6%, Shore
hardness change does not exceed 25%, tensile strength changes do not exceed 25%,
and wear resistance does not exceed 10%. .
3.4 Filling
material
3.4.1 Filling materials require good durability,
non-breaking, and no signs of weathering. The size of the filling material
should be between 1.5 Dm and 2.0 Dm (median diameter). The filler not on the
outer surface is allowed to have 15% of the super-diameter.
Figure 3.4.1 Schematic diagram of the ecological grid
1—mesh; 2—edge wire; 3—mechanical edge, wrapping the mesh on the
side wire for more than 2 weeks
3.4.2 The grading analysis of the packed stone should be carried out, and the
gradation should be reasonable. The porosity of the ecological grid structure
after filling should be less than 30%.
3.4.3 Filling materials should
choose stone materials that are not easy to weather and have good stability.
Basalt, granite and hard sandstone can meet the above requirements. Table 3.4.3
shows the severity of various types of stone. For structures with little
capacity, waste concrete blocks may be used instead of stone as fillers, but
stability analysis and weathering tests shall be carried out on site to ensure
that the strength is not lower than the strength of C20 concrete.
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Table 3.4.3 Filling material indicators
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Stone
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Severe γs(kN/m3)
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Basalt
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29.6
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granite
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26.5
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Tight limestone
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26.5
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sandstone
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23.4
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3.4.4 The filling
material of the ecological grid structure may be partially or completely
selected as a safe, stable product with water purification function, and
directly placed in any part of the ecological grid structure, and should be
placed on the surface layer.
