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Geotextiles

'''Geotextiles'''<br>

Geotextiles are filter fabrics that can be installed to separate dissimilar soils and prevent the migration of materials. Geotextiles are recommended for installation at the bottom and side limits of the LID feature and should be implemented at the discretion of the engineer.

Geotextiles are filter fabrics that can be installed to separate dissimilar soils and prevent the migration of materials. Geotextiles are recommended for installation at the bottom and side limits of the LID feature and should be implemented at the discretion of the engineer.

Construction Steps:

Construction Steps:<br>

#Roll out fabric on the flattened sub-grade surface

#Roll out fabric on the flattened sub-grade surface

#Provide a minimum overlap of 300 mm between adjacent lengths of geotextile. If the manufacturer specifies a greater overlap, follow the manufacturer’s specification

#Provide a minimum overlap of 300 mm between adjacent lengths of geotextile. If the manufacturer specifies a greater overlap, follow the manufacturer’s specification

#Provide 500 mm of excess at the ends of each length of fabric. Fold excess materiel on top of the infiltration medium/choker course once installed

#Provide 500 mm of excess at the ends of each length of fabric. Fold excess materiel on top of the infiltration medium/choker course once installed

#Provide cuts for trees and shrubs where appropriate

#Provide cuts for trees and shrubs where appropriate

#Assess on-site conditions to ensure that the tensile, tear, and puncture strength ratings of the geotextile are suitable for expected structural loads (e.g. traffic). If not properly considered, geotextiles can be adversely impacted by loading from adjacent infrastructure uses.

#Assess on-site conditions to ensure that the tensile, tear, and puncture strength ratings of the geotextile are suitable for expected structural loads (e.g. traffic). If not properly considered, geotextiles can be adversely impacted by loading from adjacent infrastructure uses<br>

Key Inspection Points:

Key Inspection Points:<br>

*Geotextile is clean and free of damage

*Geotextile is clean and free of damage

*Geotextile delivered to the site matches the design specifications and is approved by the engineer prior to installation

*Geotextile delivered to the site matches the design specifications and is approved by the engineer prior to installation

*Geotextiles have been applied as per the manufacturer’s guidelines

*Geotextiles have been applied as per the manufacturer’s guidelines

*Structural considerations for geotextiles have been made when applied adjacent to infrastructure and the geotextile can handle expected structural loads

*Structural considerations for geotextiles have been made when applied adjacent to infrastructure and the geotextile can handle expected structural loads

*Class II geotextiles conform to OPSS 1860

*Class II geotextiles conform to OPSS 1860<br>

Mistakes to Avoid:

Mistakes to Avoid:<br>

*Wrinkles in the fabric – follow the manufacturer’s procedure for installation to ensure geotextiles lie smooth on sub-grade

*Wrinkles in the fabric – follow the manufacturer’s procedure for installation to ensure geotextiles lie smooth on sub-grade

*Unnecessary application of geotextile – mixing of media is negligible where structural loads are not expected, so geotextile does not need to be applied. Also, geotextiles should not be used where root growth is encouraged to penetrate different layers of media  

*Unnecessary application of geotextile – mixing of media is negligible where structural loads are not expected, so geotextile does not need to be applied. Also, geotextiles should not be used where root growth is encouraged to penetrate different layers of media<br>

Where structural loads are anticipated or underlying soil is particularly soft, geogrid can be applied in conjunction with geotextile. Geogrid is a rigid geosynthetic material that can be laid on sub-grade to reinforce softer soils and provide a more even distribution of loads across the sub-grade materials.

Where structural loads are anticipated or underlying soil is particularly soft, geogrid can be applied in conjunction with geotextile. Geogrid is a rigid geosynthetic material that can be laid on sub-grade to reinforce softer soils and provide a more even distribution of loads across the sub-grade materials.<br>