# Feotechnical Engineering

Topics: Geotechnical engineering, Retaining wall, Soil Pages: 3 (895 words) Published: February 12, 2013
Assignment No. 3
CE 332: Geotechnical Engineering

1. Calculate the vertical stress in a soil mass at a depth of 5m vertically below a point load of 5000 KN acting near the surface. Plot the variation of vertical stress with radial distance (up to 10 m) at a depth of 5 m.

2. Three point loads 10000 KN, 7500 KN and 9000 KN, act in line 5 m apart near the surface of soil mass. Calculate the vertical stress at a depth of 4 m vertically below the centre (7500 KN) load.

3. Determine the vertical stress at a depth of 3 m below the centre of a shallow foundation 2m x 2m carrying a uniform pressure of 250 KN/m2. Plot the variation of vertical stress with depth (up to 10 m) below the centre of the foundation.

4. A shallow foundation 25 m x 18 m carries a uniform pressure of 175 KN/m2. Determine the vertical stress at a point 12 m below the mid-point of one of the longer sides (a) using influence factors, (b) by means of Newmark’s chart.

5. The backfill behind a retaining wall above the water table consists of a sand of unit weight 17 KN/m3, having shear strength parameters c / = 0,φ / = 370 . The height of the wall is 6 m and the surface of the wall backfill is horizontal. Determine the total active thrust on the wall according to the Rankine theory. If the wall is prevented from yielding, what is the approximate value of the trust on the wall?

6. Plot the distribution of active pressure on the wall surface shown in Figure 1. Calculate the total trust on the wall (active + hydrostatic) and determine its point of application. 7. The front of a retaining wall slopes outwards at an angle of 100 to the vertical. The depth of soil in front of the wall is 2 m, the soil surface being horizontal and the water table is well below the base of the wall. The following parameters are known for the soil: c / = 0,φ / = 340 , δ = 150 , γ = 18KN / m3 . Determine the total passive resistance available in front of the wall (a) according to Coulomb’s theory, (b) using Sokolovski’s...