Hydrophobic material used for drainage of culvert.

摘要

A hydrophobic material (A) is used in the drainage of a culvert in which a soil aggregating agent (2) is introduced into the fine mesh portion (4) of a textile or knitted fabric (1) which comprises both fine mesh portions (4) and coarse mesh portions (5). The fabric (1) may be covered by a water soluble film (3) and may be formed of a degradable material. In this way the soil aggregating agent is dissolved by the surrounding water and penetrates the soil so as to impede the break-up of the soil clods and retain the permeability of the soil (7).