GRP Pipe

Pipe BurialProper pipe burial requires choosing the appropriate fill material for the soil type.When the natural soil can be used, it must be free of any rocks or other organic content. The following pipe installation options table enables choosing the most appropriate coverage type, considering the pipe's stiffness and the coverage height required above the pipe's vertex.Proper pipe installation and maintenance ensure GRP pipelines will have a long lifespan.Granular material for filling around the pipe is ideal for GRP pipes and enables excellent pipe and soil system performance.

SN 2500SN 5000SN 10000StiffnessInstallation Type

81216

Maximumcoverage height

(in meters)

71014

5812

3610

NRNR3

*Maximum coverage height in metersThe table represents five types of installation. Other installation types are also available

Clean sand contains less than 12% fines, 90% SPD

90% sand SPD or 70% gravel RD

Loose sand

Natural soil

Gravel density over 70% RD

Fibertech Industr ies Fiberglass Pipes Ltd. | Tel : 09-7929441 | Fax: 09-7929442 | www.f ibertech.co. i lF ibertech Industr ies Fiberglass Pipes Ltd. | Tel : 09-7929441 | Fax: 09-7929442 | www.f ibertech.co. i l

GRP Pipes

General Fill Materials Recommendations for Pipe TrenchesThe general recommendation for fill materials depends on the type of soil where the pipe is laid.

Where the soil content is heavy with loam, organic material or underground water (or a combination of these), the soil consultant's instructions must be followed to establish the infrastructure of the trench. The acceptable materials used for establishing the infrastructure include gravel, broken rock, sand and more. In special cases, the infrastructure will require coverage with geotextile and additional foundation treatments.Placing Pipes in Underground WaterDespite the difficulty of placing pipes in underground water, the weight above the pipe must be at all times greater than the lift-force impacting an empty pipe (flooded pipe condition). To ensure this condition is met, the specific gravity of the soil above the pipe must be 1900 kg per cubic meter. The rule of thumb is that the minimal coverage height should equal 1.5 times the pipe's diameter.SubbaseThe pipe's subbase should be a 15 cm thick granular material.Occasionally, when the soil is unstable or has rocks in it, the trench's floor must be deepened further and the subbase layer increased, to provide support for the pipe.

Principle Recommendationfor Pipe Trench Filling

Pipe Trench WidthDescription of SoilSoil Type

Trench infrastructure treatment according to the planner's instructions. Replacement of soil in pipe trench with sand.

Compacted sand filling up to 30 cm above the pipe's vertex. Pursued by an appropriate subbase fill material.

2 X O.D

Small grains in soil. Medium to high plasticity.

Over 50% moisture content.

Loam.

Infrastructure treatment, including subbase construction, according to the planner's instructions. Replacement of

soil in pipe trench with sand. Compacted sand filling up to 30 cm above the pipe's vertex, pursued by an appropriate

subbase fill material.

2 X O.D

Small grains in soil. No plasticity up to medium

plasticity. Less than 25% rough particles. Less than

50% moisture content.

Red loam

Infrastructure treatment, including subbase construction, according to the planner's instructions. Replacement of

soil in pipe trench with sand. Compacted sand filling up to 30 cm above the pipe's vertex, pursued by an appropriate

subbase fill material.

2 X O.D

Small grains in soil. No plasticity up to medium

plasticity. Over 25% rough particles. Less than 50%

moisture content.

Silt

Local subbase material is used for filling the pipe trench. (Clean organic subbase and rock material, as detailed)1.5 X O.DRough grains in soil. Over

12% finesSand

Local subbase material is used for filling the pipe trench. (Clean organic subbase and rock material, as detailed)1.5 X O.DRough grains in soil. Less

than 12% fines.Sand gravel

Local subbase material is used for filling the pipe trench. (Clean organic subbase and rock material, as detailed)1.5 X O.DCrushed rockFine gravel

Calculating the Breadth of the TrenchDN (mm)A(mm)

300150

350-500200

600-900300

1000-1600450

1800-2400600

2800-4000900

Fibertech Industr ies Fiberglass Pipes Ltd. | Tel : 09-7929441 | Fax: 09-7929442 | www.f ibertech.co. i lF ibertech Industr ies Fiberglass Pipes Ltd. | Tel : 09-7929441 | Fax: 09-7929442 | www.f ibertech.co. i l

GRP Pipe

Deformation During Pipe InstallationThe maximum allowed deformation when installing the pipeline (after final coverage completion); maximum deformation in the long run will not exceed 5%.

Maximum Deformation in %Natural Soil Types BLOW COUNT3Very tough30<

3Tough16-30

2.5Medium6-15

2Soft3-5

Minimum Coverage Height

(in meters)Vehicle Type Load Type

Trucks AAHO H2O

0.5 Heavy trucks HA153 BS

Train COOPTR E 80RR

GC/SC

GW – Well-graded gravel

GP – Poor graded gravel

SW – Well graded sand

SP – Poor graded sand

SW – GC

SP – SMGC - GM

CL - Lean clay

ML – Silt

ML – Cl

GM – Silty gravel

GC – Clayey gravel

SM – Silty sand

SC – Flayey sand

Fill MaterialTo ensure the pipeline system has a good foundation, granular material should be used. When the natural soil can be used, it must be free of any rocks or other organic content. Optional fill materials according to Standard AWWA M45.

Surface LoadsFibertech pipes are suitable for vehicle loads above the load classification level

For live loads verify the material is compressed around the pipe. Minimum coverage height can be reduced with special foundation such as cast concrete over the pipe and around it.

Fibertech Industr ies Fiberglass Pipes Ltd. | Tel : 09-7929441 | Fax: 09-7929442 | www.f ibertech.co. i lF ibertech Industr ies Fiberglass Pipes Ltd. | Tel : 09-7929441 | Fax: 09-7929442 | www.f ibertech.co. i l