Question

Calculate the settlement of a foundation supported on a sand stratum using the Schmertmann method. Square foundation 3 m by 3 m, foundation bearing capacity q 165 kPa, installation depth D 1.5m

Answer 1

Step-by-step explanation:

From the given information:

The square foundation = 3m by 3m

capacity q = 165 kPa

depth = 1.5 m

assuming soil unit weight = 17.5 kN

q = 17.5 × 1.5

q = 26.25 kPa

Settlement
`Se = C_1C_2 (\overline q - q) ((I_z)/(E_s))D_f`

where;

`c_1 = 1-0.5 ((q)/(\overline q -q))`

`c_1 = 0.905`

`c_2 = 1+ 0.2 log ( (t)/(0.1))`

suppose t = 1year

`c_2 = 1+ 0.2 log ( (1)/(0.1))`

`c_2 = 1.2`

Using Schertmann method.

`\mathtt{ I_t = 0.5 }`

`(length )/(breadth ) = (3)/(3)=1`

∴

E⁵ =
`2.5 q_e`

E⁵ = 2.5 × 165

E⁵ = 412.5 kPa

Hence:
`Se = C_1C_2 (\overline q - q) ((I_z)/(E_s))D_f`

`Se = 0.905 * 1.2(165-26.25) ((0.5)/(412.5))*1.5`

`\mathbf{Se = 0.273 \ m}`