In this post, we want to take a closer look at what wick drain is, how to install wick drains, how to select a wick drain installation equipment and the benefits of wick drain installation machine that focus on helping consolidate the soil faster.
Wick Drain (Prefabricated Vertical Drain = PVD), also known as Band Drain, are polypropylene wicks that function as free drainage waterways, contain flexible, longitudinal channels and provide high water flow.
These wicks are covered with a fine geosynthetic filter. These wick drains have a width of approximately 100 mm (4-inch) and a wall thickness of 3 mm (1/8-inch).
In some special applications, these features may differ. Water drainage capacities of PVDs should be at least 5.7 liters/min at 275 kPa (40 psi) according to ASTM D4716.
How Does Wick Drain Help Consolidate The Soil Faster?
The difficulties experienced by engineers in the design of structures built on loose and liquid soils have necessitated various improvement methods throughout history. Unpredictable long-term ground settlements cause unnecessary labor and additional costs, as well as a waste of time.
Simple and ordinary ground consolidation works can take quite a long time. This waste of time can be overcome by creating artificial vertical drainage paths through which water flow can be achieved.
Wick drains, also known as prefabricated vertical drains (PVD), are designed to provide drainage paths for drain water in loose (cohesive) soils.
It takes years for some soils to reach 90% of the settlement. Therefore, in order to accelerate the settlement, the groundwater should be discharged to the outside and the soil should be compressed.
In order to remove groundwater, vertical drains must be placed on the ground to ensure the movement of water. These drains, like a filter, allow it to be transported to the ground surface through channels.
Prefabricated Vertical Drains (band drain-wick drain) which are used in the ground consolidation process not only saves time but also reduce operating costs. Because drainage materials shorten and facilitate the flow of water, accelerate ground consolidation, and groundwater is quickly discharged.
In this way, the equipment that is required is also reduced. With the OMS Wick Drain Installation Machine, the most efficient results are obtained at a low cost.
How to Select A Wick Drain Installation Machine?
Although there are various methods for placing a Band/Wick drain into the ground, the most suitable method is to use equipment that can apply both static pressure force and dynamic pressure force (like an OMS Vibro Hammer).
Since the geology can differ within layers, and when its harder or cohesive soil is encountered the equipment working with only static load may not be effective and therefore OMS Wick Drain Installation Machines can provide this combination (static and dynamic force), so it is advantageous than the other types.
OMS, which is in the leading position among the companies producing equipment in the ground improvement sector, has designed wick drain installation machines by targeting high water flow capacity, high resistance filtering features and durable structures.
It is a great advantage for its users that the OMS wick drain equipment, which is produced to provide easy assembly and application convenience, can be installed on all excavators with sufficient tonnage and capacity.
How To Install Wick Drains?
- Wick drains in rolls are installed in the drain drum located on the machine.
- Sand, gravel, or suitable materials, materials are also called drain blankets shortly, are laid on the ground to be placed in the wick drain.
- The system is rigging to a vertical position with the help of an excavator. The product is ready for operation.
- The specially designed button type mandrel is driven to the desired depth by the OMS Wick Drain Installation Machine. After installing the mandrel, PVD material leaves into the ground.
- This operation is repeated at each predetermined drainage. In different areas of application, the depth at which the operation should be performed may vary.
- After the installation of all the drains is completed, the ground should be loaded with earth material required by the project. The groundwater rises to the surface through the drains.
The time of the soil consolidation process using the Wick Drain method has been significantly reduced. Thus, the ground consolidation operations, which have been going on for years, have been completed within a few months.
How To Install Wick Drains Video?
Where Are Wick Drains Used?
Wick drain can be applied in all areas requiring ground consolidation, including the following areas;
- Highway walls/embankments/ impoundment,
- Bridge roads/routes and crossings,
- Airports and harbors/ports,
- Storage tanks,
- Mining waste ponds.