2450 2400 E 2350 Dry unit weight, (kg/m³) 2300 2250 2200 2150 2100 4 5 6 7 8 9 10 11 12 Water content (%)

. The wet density of a sample of sand found at a site is 1.85 Mg/cubic meter with a water content of 12%. The specific gravity is 2.71 (Mg/cubic meter). The maximun and minimum void ratios are 0.65 and 0.38, respectivily. Calculate the relative density of the sand at the site.

The results of a laboratory consolidation test on a clay specimen are the following. Pressure, ir (lb/ft²) 500 1.000 2.000 4.000 8,000 16.000 Total height of specimen at end of consolidation (in.) 0.6947 0.6850 0.6705 0.6520 0.6358 0.6252 Given the initial height of specimen = 0.748 in.. G specimen = 95.2 g. and area of specimen = 4.91 in.²: a. Plot the e-log or curve = 2.68. mass of dry b. Determine the preconsolidation pressure c. Calculate the compression index, C.

A proposed fill is to be placed on the soil profile shown in Figure 3.9. A consolidation test has been performed on a sample obtained from Point A, and this test indicates the preconsoli- dation pressure at that point is 200 kPa. Determine whether the silty clay stratum is normally consolidated or overconsolidated, and compute the o solidation ratio. The proposed fill has not yet been placed. overcon- Hint: Determine EFFECTIE STRRESS ATA water > leval 1.2m Silty Y = 19.1 kN/m 1.0m. Sand (SM): Y = 20.2 kN/m? 20 M Silty Clay (CL) Y=17.8 kN/m Figure 3.9 Soil profile for Example 3.3.

We know that

3-8 A 1-ft3 of undisturbed soil sample has a dry weight of 107 lbs. The specific gravity of the soil solids is 2.70. Need Vs VT = 1 To solve for Vs = use the following equation Ws=Vs*Gs*yw (solve for Vs) a) Calculate the void ratio of the sample. b) Calculate the porosity of the sample. DC

A large oil storage tank 90 meters in diameter is to be constructed on the soil profile shown in the figure below. The average depth of the oil in the tank is 18 meters, and the specific gravity of the oil is 0.92. Consolidation test showed that the clay is normally consolidated with Ccε = 0.154, Crε = 0.0112, and σ'p = 260 kPa. Estimate the total consolidation settlement of the tank. Neglect any settlements in the sand (ρd,sand = 1.71 Mg / m3). Perform this estimation by: a. Assuming conditions at the mid-depth of the clay are typical of the entire clay layer. b. Dividing the clay layer into four thinner layers with a thickness of 5 meters each, computing the settlement of each thin layer, and summing up using the included equation for sc. Assume that σ'p = σ'vo when σ'vo > σ'p. Hint: the load applied by the tank is given by qo = ϒoilhoil

A soil sample is having void ratio 0.9 and volume 5 m3. Upon compaction, void ratio of the sample is reduced by 0.2. Determine the percent change in volume due to compaction.

Note) For soil sample in Table 2, initial thickness of sample = 14.31 mm, sample area = 2827.433 mm^2, dry weight measured at the end of test = 52.53 g, specific gravity = 2.7 Also, Determine the compression index and expansion index Please show graph