A 5-m high retaining wall with a vertical back and an inclined backfill is shown in the figure below. The inclination of the backfill with the horizontal is 15°.
A. If the wall is considered frictionless, find the magnitude and location of the Rankine active force Pa per unit length of the wall after the occurrence of the tensile cracks. B. If the wall is frictional and the angle of wall friction 5 = 15°, calculate the active force per unit length of the wall and the location of the force, using Coulomb's equation.
Problem (2) (20 points)
A clay slope is built over a layer of rock. The height of the slope is 12 m and the slope angle p = 30°.
Determine the factor of safety if kh=0.4 for the slope. The soil properties are: saturated unit weight VSAT = 18 kN/m3 and the undrained shear strength cu = 40 kN/m2.
Problem (3) (20 points)
A square footing is founded at a depth of 0.92 m below the ground surface. Due to inadequate drainage, the ground water table is located at the ground surface. The subsoil is cohesionless with ysAT = 18.5 kN/m3 and 0' = 40°. The footing must carry a gross allowable load of 700 kN with factor of safety of 3. Find the required size of the footing using Terzaghi's general shear failure theory.
Attachment:- HW #3.pdf