Soil and Foundation Engineering

A braced cut, 5m wide and 7.5 m deep is proposed in a cohesionless soil deposit having effective cohesion c’=0 and effective friction angle,^$\phi$’=36⁰. The first row of struts is to be installed at a depth of 0.5 m below ground surface and spacing between the struts should be 1.5 m. If the horizontal spacing of struts is 3 m and unit weight of the deposit is 20 kN/m³, the maximum strut load will be

At a reclamation site for which the soil strata is shown in figure, a 3 m thick layer of a fill material is to be laid instantaneously on the top surface. If the coefficient of volume compressibility, m_v for clay is 2.2 x 10^-4 m²/kN, then the consolidation settlement of the clay layer due to placing of fill material will be

While designing a hydraulic structure, the piezometric head at bottom of the floor is computed as 10 m. The datum is 3 m below floor bottom. The assured standing water depth above the floor is 2 m. The specific gravity of the floor is computed as 10 m. The datum is 3 m below floor bottom. The assured standing water depth above the floor is 2 m. The specific gravity of the floor material is 2.5. The floor thickness should be

The plan area of a reservoir is 1 km². The water level in the reservoir is observed to decline by 20 cm in a certain period. During this period the reservoir receives a surface inflow of 10 hectare-meters, and 20 hectare-meters are abstracted from the reservoir for irrigation and power. The pan evaporation and rainfall recorded during the same period at a near by meteorological station are 12 cm and 3 cm respectively. The calibrated pan factor is 0.7. The seepage has from the reservoir during this period in hectare-meters is

A canal having side slopes 1:1 is proposed to be constructed in a cohesive soil to a depth of 10 m below the ground surface. The soil properties are: ^$\phi_u$=150, C_n = 12 kPa, e = 1.0, Gs = 2.65.

If Taylor’s Stability Number, Sn is 0.08 and if the canal flows full, the factor of safety with respect to cohesion against failure of the canal bank slopes will be

Figure shows the geometry of a strip footing supporting the load bearing walls of a three storied building and the properties of clay layer.

If the elastic modulus and the Poisson’s ratio of the clay layer are respectively 50×10³ kPa and 0.4 and if the influence factor for the strip footing is 1.75, the elastic settlement of the footing will be

A canal having side slopes 1:1 is proposed to be constructed in a cohesive soil to a depth of 10 m below the ground surface. The soil properties are: ^$\phi_u$=150, C_n=12 kPa, e = 1.0, Gs = 2.65.

If there is a sudden drawdown of water in the canal and if Taylor’s Stability Number for the reduced value of ^$\phi_u$is 0.126, the factor of safety with respect to cohesion against the failure of bank slopes will be

Column I below gives a list of physical properties of aggregates which should be determined to judge their suitability in road construction. Column II gives a list of laboratory tests which are conduced to determine these properties.

Which of the following matches is correct?

A double draining clay layer, 6 m thick, settles by 30 mm in three years under the influence of a certain loads. Its final consolidation settlement has been estimated to be 120 mm. If a thin layer of sand having negligible thickness is introduced at a depth of 1.5 m below the top surface, the final consolidation settlement of clay layer will be