Design a 5-m high wraparound woven geotextile reinforced soil wall
carrying a road consisting of 25-cm stone base ( = 21.2 kN∕m³) and
12.5-cm asphalt ( = 24.0 kN∕m³). The wall is to be backfilled with
sand of = 18.0 kN∕m³, ′ = 35°, and c′ = 0. The external friction
angle between the soil and geotextile is = 25°. The geotextile has
an ultimate tensile strength of 50 kN∕m. Use reduction factors for
installation damage, creep, and chemical/biological degradation. The
factor of safety for tensile strength is 1.5.
Determine:
(1) How many layers of geotextile are needed and the vertical spacing
of each layer.
(2) Geotextile embedment length of each layer.
(3) Geotextile overlap length of each layer.
(4) The external stability in terms of overturning, sliding, and bearing
capacity of the MSE wall that you designed in (1)–(3). The foun-
dation soil is ML-CL with = 18.8 kN∕m³, = 15°, d = 0.9, c =
500 psf, andca = 0.90c.
