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.

Respuesta :

Answer:

magnitude of thrust uis  11061.65 lb/ft

location is 5 ft from bottom

Explanation:

Given data:

Height of vertical wall is 15 ft

OCR  is 1.5

[tex]\phi = 33^o[/tex]

saturated uit weight[tex] \gamma_{sat} = 115.0 lb/ft^3[/tex]

coeeficent of earth pressure [tex]K_o[/tex]

[tex]K_o = 1 -sin \phi[/tex]

        = 1 - sin 33 = 0.455

for over consolidate

[tex]K_{con} = K_o \times OCR[/tex]

            [tex] = 0.455 \times 1.5 = 0.683[/tex]

Pressure at bottom of wall is

[tex]P =K_{con} \times (\gamma_{sat} - \gamma_{w}) + \gamma_w \times H[/tex]

   [tex]= 0.683 \times (115 - 62.4) \times 15 + 62.4 \times 15[/tex]

P = 1474.88 lb/ft^3

Magnitude pf thrust is

[tex]F= \frac{1}{2} PH[/tex]

   [tex]=\frac{1}{2} 1474.88\times 15 = 11061.65 lb/ft[/tex]

the location must H/3 from bottom so

[tex]x = \frac{15}{3} = 5 ft[/tex]