Geotechnical Engineering Practice Test 7

1. When the maximum vertical stress \((σ_z)_{max}=\frac{0.0888Q}{r^2}\) at a point, the shear stress at that point is ____________

\(τ_{rz}=\frac{0.0725Q}{r^2} \)

\(τ_{rz}=\frac{0.0888Q}{r^2} \)

\(τ_{rz}=\frac{0.234Q}{r^2} \)

\(τ_{rz}=\frac{0.328Q}{r^2} \)

2. The radial stress component σ_r due to inclined line load of intensity Q per unit length is given by ___________

\(σ_r=\frac{2Q}{r}(\frac{cosβcosθ}{2α+sin2α})\)

\(σ_r=\frac{2Q}{r} (\frac{cosβcosθ}{2α+sin2α}+\frac{sinβsinθ}{2α-sin2α})\)

\(σ_r=\frac{Q}{r} (\frac{cosβcosθ}{2α+sin2α}+\frac{sinβsinθ}{2α-sin2α})\)

\(σ_r=\frac{2Q}{r}(\frac{sinβsinθ}{2α-sin2α})\)

3. In Terzaghi’s Theory of one dimensional consolidation, excess pore water drains out in __________

horizontal direction only

both horizontal and vertical direction

tangential direction only

vertical direction only

4. The vertical stress is proportional to __________

\(\frac{z^2}{K_B} \)

\(\frac{z^3}{K_B} \)

\(\frac{K_B}{z^2} \)

\(\frac{K_B}{z^3} \)

5. In Newmark’s influence chart method, the point below which pressure is required should lie within the loaded area.

False

True

6. The uniformly varying load is __________ in a beam.

rate of loading increases non-linearly from zero

rate of loading increases linearly from zero

equal load only at supports

equal load at every point

7. In Terzaghi’s Theory of one dimensional consolidation, the time lag in consolidation is ___________

due entirely to permeability of soil

due entirely to viscosity of water or fluid

due entirely to seepage pressure of water

due to permeability of soil and viscosity of water or fluid

8. If r/z ratio is 0.5 and load of 20 kN is acting at a point, then the vertical pressure at a depth 6m is ____________

0.4356 kN/m²

0.244 kN/m²

0.597 kN/m²

0.1518 kN/m²

9. At a certain point within soil mass, the stresses are caused only because of surface loadings.

False

True

10. If z-axis is considered to be directed downward from ground surface, then the stress component in z-axis at a point at a depth z due to self weight of soil above it is ___________

σ_z=\(\frac{μ}{1-μ}γz \)

σ_z=μγz

σ_z=\(\frac{μ}{1-μ}\)

σ_z=γz