Apr 14, 20202 min
Updated: Apr 27, 2020
181. Degree of freedom of a block type machine foundation is
182. Given that damping ratio = 0.10 and damping coefficient = 225 kN sec/m.
Then the critical damping coefficient in kN sec/m will be 2250
183. The natural frequency of a vibrating foundation system
i) increases as the square root of the
ii) decreases with the square root of the\ mass of the body
184.In case of free over damped vibration
185. As per converse Labarre formula, group efficiency offrictionpiles is given by:
186. The correct increasing order of the surface areas of the given soils is
sand, silt, clay, colloids
₁₀ ₂₀ ₃₀ ₄₀ 𝒸 ᵤ
187. For a given soil sample,
C𝒸 = coefficient of gradation
Cᵤ = coefficient of uniformity
D₁₀ = effective size
D₃₀ = diameter through which 30 per cent
of the total soil mass is passing
If C𝒸 = 1.0 and cᵥ, = 4.0, then the value of
D₃₀/D₁₀ would be
188.
Stoke- Velocity of settling particle
Darcy- Flow of water through a soil mass
Poiseuille- Flow through capaillary
Atterberg-Consistency limits
189. In a standard Proctor compaction, the water content (w) and maximum dry
density (γdmax) are related a
γdmax corresponds to a unique value of w
190. Using Mohr's diagram, the relation between major principal stress oi, and
minor principal stress σ₁ and σ₃shear parameters c and Φ is given by
(1 +sinΦ)/(l-sinΦ)
191. A and B are Skempton's pore pressure parameters and Δσ₁ and Δσ₃ are
incremental principal stresses. Skempton's pore pressure equation is given by
Δu = B[Δσ₃ + A(Δσ₁ - Δσ₃)]
192. The total settlement of a compressible soil stratum 2 m deep and having a coefficient of volume compressibility of 0.02 cm²/ kg under a pressure increment of 2 kg/cm will be 8 cm
193. Given that for a single degree of freedom system,
k = stiffness coefficient
m = mass of machine and foundation,
critical damping is best defined by the
expression 2√km
194.The relationship between water content (w%) and number of blows (N) in soils, as obtained from Casagrande's liquid limit device, is given by
w = 20 - log₁₀ N
The liquid limit of the soil is 18.6%
195. The results (curves A,B,C and D) of four compaction tests on different soils are
shown in Fig. 8.3
1. Silty sand, modified test
2. Silty sand, standard test
3. Fat clay, modified test
4. Fat clay, standard test
196. The results of a consolidated drained triaxial shear test on a normally
consolidated clay are shown in Fig.8.4
The angle of internal friction is
197.Which one of the following statements provides the best argument that direct
shear tests are not suited for determining shear parameters of a clay soil ?
Pore pressures developed cannot be measured.
198.
199.Two specimens of clay A and B are tested in a consolidation apparatus.
If(mv)A = 3.6x l04m²/kNand
(mv)B= l.8x l0⁻⁴ m²/ k N ,
(Cv)A = 3.8x l0⁻⁴ cm²/s,
(CV)B= l.9x l0⁻⁴ cm²/s,
4
200.Terzaghi's equation of ultimate bearing capacity for a strip footing may be used for square footing resting on pure clay soil with the correction factor
1.3