Prefabricated Vertical Drains
Prefabricated vertical drains provide drainage paths through compressible ground to accelerate consolidation under an engineered preload. We manufacture and supply the drains and coordinate specialist installation to the geotechnical design.
Product description and supply
A prefabricated vertical drain is a narrow polymeric drainage core enclosed by a geotextile filter. Installed into suitable compressible ground, it provides a shorter route for pore water to move toward the designed drainage system during consolidation.
Geosynthetics South Africa manufactures and supplies PVDs through our factories, with the specified core, filter and production controls. The project design and specialist installation method determine the drain arrangement and required performance.
Performance under field conditions
The product submission should address discharge capacity under confinement, filter properties, core and jacket integrity, tensile behaviour and the effect of deformation. The specified test pressure, gradient and specimen condition are necessary to interpret a discharge value.
Consider the deformation and kinking expected as the ground settles. A straight unconfined laboratory flow result should not be treated as the installed design capacity.
Applications and uses
We supply and install this product for:
- Acceleration of consolidation in compressible ground under an engineered preload or surcharge.
- Ground improvement beneath embankments, reclamation and infrastructure platforms.
Why choose Prefabricated Vertical Drains?
- Drainage paths through compressible soils
- Manufacture and project quantities
- Specialist installation support
Installation and technical guidance
Installation and QA/QC
Send the geotechnical report, drain schedule, specified construction, roll requirements and project programme. The drain installation contractor should confirm rig compatibility, anchors, splices, installation depth and handling requirements before supply.
Our manufacturing and supply quotation identifies the product scope and delivery schedule. Specialist mandrel installation, surcharge construction and instrumentation are separately defined activities rather than assumed inclusions.
Require traceable production and delivery records. The installation plan should record drain positions, depths, refusals, splices and departures from the specified grid. Approve the drainage blanket and discharge route before loading.
Settlement plates, piezometers and other monitoring, where specified, help the engineer assess the response to staged construction. The drain product alone cannot establish when the required consolidation has been reached.
Specification and quotation inputs
| Item | Confirm for this project |
|---|---|
| Ground conditions | Soil profile, permeability, groundwater, compressibility and settlement criteria. |
| Drain performance | Discharge under specified pressure and deformation; filter and tensile requirements. |
| Installation | Drain grid, depths, mandrel, anchor and splice details. |
| System interfaces | Working platform, drainage blanket, outlets and surcharge sequence. |
| Acceptance | Production tests, installation logs and geotechnical monitoring requirements. |
Match the exact supplied grade to current documentation and the approved project specification. Product availability and lead time are confirmed with the quotation.
Questions engineers and contractors ask
How long will consolidation take?
It depends on the soil profile, drainage spacing and length, loading sequence and design assumptions. Use the project geotechnical design and monitoring data, rather than a generic promised completion time.
Do you manufacture and install the drains?
Our established scope includes Manufacturing across our factories and supply. The quotation must separately identify specialist installation and monitoring responsibilities.
Can wick drains replace a surface drainage blanket?
The functions differ. The design must provide a route from the vertical drains through the collection layer to a suitable discharge point.
Choose the scope you need
Supply only; manufacture or fabrication; supply and delivery; or supply with a defined installation and QA/QC scope. The quotation identifies materials, responsibilities, testing and the required handover records.
Design and procurement inputs
Drain spacing, depth, installation method, smear effects, discharge capacity and instrumentation belong to the geotechnical design. Vertical drains do not independently provide bearing capacity.
Provide the product grade or performance specification, drawings or BOQ, quantities, site location and required date. We will define supply, delivery and any agreed installation and QA/QC responsibilities in the quotation.
Request a product-specific quotation →Technical documentation and specification support
Request the current supplied-grade datasheet, applicable installation guidance and supporting quality records from our technical team.