Select geotextile meeting the criteria of typical tender requirements (following SB250, SB260,.. )

k in m/s

M-factor gtx in relation

Velocity index V in m/s

Thickness under 2kPa in m

Permittivity 𝛹 in 1/s

Number

Scientific

Heavy Clay

Sandy Clay

Sand

Sandy Gravel

Gravel

M = Safety factor

Roads M>10

Hydraulic works, drainage M>100

Unsuitable M<10