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.