In order to construct drainage and water diversion systems, it is necessary to identify the material possessing the required extent of strength and water permeability. Thermally bonded geotextile is capable of performing a filtering function with strength performance intact, therefore it is widely used in construction.
Contents
Application
Nonwoven thermally bonded geotextile is used as a filtering material in construction of drainage systems and water evacuation systems of either open or close type.
Clogging of a drainage system or filtering material can lead to substantial escalation of ground water level at a large area. The filtering geotextile is designed to protect drainage systems and drain pipes from clogging by soil particles or wash-out.
Thermally bonded geotextile is marketed as Geospan BB in the Geospan range. This material has the necessary physical and operational properties. Its structure puts no obstacle to the water flow, is not susceptible to silting and maintains the filtering aperture shape under the working pressure.
Geospan BB manufacturing process implies the material production by passing a fabric through a calender hot bowls. This operation is called thermal calendering.
Laying techniques
Let’s consider nonwoven heat-bonded geotextile laying techniques through an example of building a drainage system to evacuate water off a settlement road.
First, one has to dig a 50 cm-deep trench, with filtering thermally bonded geotextile unrolled on its bottom. Then it should be topped with coarse sand. Coarse sand is a secondary rock decomposition product with a grain size varying from 2.5 mm to 3.5 mm. Next, another geotextile fabric should be unrolled over the sand thus forming a casing.
At the end, the trench should be filled with stone screening dust. Stone screening dust is a construction material produced by processing of rocks.
Track record
Geotextile materials can be used either in road construction or building sport facilities, landscaping and other applications. Below are some examples of Geospan BB heat-bonded nonwoven geotextile usage in specific projects.
A football pitch in Rostov-upon-Don. Geospan BB 90 was utilized in the pitch development as a separation and draining layer. This allowed strengthening of the football pitch and unrestricted moisture outflow to avoid puddles.
An artificial football pitch in Adygeya. Geospan BB was used as a drainage layer in the pitch construction.
Landowners’ park in Tatarstan. Geospan BB was used for dewatering purposes while making a drainage system.
White Dews residential complex in Krasnoyarsk. Geospan BB geotextile was placed as a backflow filter under a geogrid while constructing an onshore on the Enisej river bank.
Use the link to see the full list.
Conclusions
Drainage systems and water-diverting structures using non-woven thermally bonded geotextiles are a proven and reliable method for lowering groundwater levels and transferring rainwater and meltwater from drainage systems to discharge points
