Question

A 15 ft high vertical wall retains an overconsolidated soil where OCR-1.5, c'-: O, ф , --33°, and 1 1 5.0 lb/ft3.

Determine the magnitude and location of the thrust on the wall, assuming that the soil is at rest.

Answer 1

magnitude of thrust uis 11061.65 lb/ft

location is 5 ft from bottom

Step-by-step explanation:

Given data:

Height of vertical wall is 15 ft

OCR is 1.5

`\phi = 33^o`

saturated uit weight
`\gamma_(sat) = 115.0 lb/ft^3`

coeeficent of earth pressure
`K_o`

`K_o = 1 -sin \phi`

= 1 - sin 33 = 0.455

for over consolidate

`K_(con) = K_o * OCR`

`= 0.455 * 1.5 = 0.683`

Pressure at bottom of wall is

`P =K_(con) * (\gamma_(sat) - \gamma_(w)) + \gamma_w * H`

`= 0.683 * (115 - 62.4) * 15 + 62.4 * 15`

P = 1474.88 lb/ft^3

Magnitude pf thrust is

`F= (1)/(2) PH`

`=(1)/(2) 1474.88* 15 = 11061.65 lb/ft`

the location must H/3 from bottom so

`x = (15)/(3) = 5 ft`