Problem E A 4-meter-thick sand overlies a thick layer of clay. The water table is 1.80 meters below the sand surface. The sand has a porosity of 34.64% and a degree of saturation is limited to 36.0% above the water table. The clay has a moisture content of 45.0% and the specific gravity of both sand and clay is 2.68. a. Total Stress at a point 12.0 meters below the sand surface. b. Total Effective Stress at a point 12.0 meters below the sand surface.

Subject is soils mechanics

Weight of structure W.T. Sand layer H2 Clay layer Н as Compacted sand- gravel layer figure 1

A certain saturated sand (S = 100%) has a moisture content of 27.9% and a specific gravity of solids of 2.61. It also has a maximum index void ratio of 0.90 and a minimum index void ratio of 0.33. Compute its relative density and classify its consistency. (Table on the right) Solution: Given the values of mmoisture content, specific gravity and degree of saturation, the void ratio can be estiamted as: e = Thus the relative density is found to be Dr = • According to the table, the soil is classified as %; soil. TABLE 3.3 CONSISTENCY OF COARSE-GRAINED SOILS AT VARIOUS RELATIVE DENSITIES (data from Lambe and Whitman, 1969) Relative Density, D,(%) 0-15 15-35 35-65 65-85 85-100 Classification Very loose Loose Medium denseª Dense Very dense "Lambe and Whitman used the term "medium," but "medium dense" is better because "medium" usually refers to the particle size distribution.

Situation 5 : A sample of saturated clay was placed in a container and weighed. The weight was 6N. The clay in its container was placed in an oven dray for 24 hours @ 105℃. The weight reduced to a constant weight of 5N. The weight of the container is 1N. If Gs = 2.7, determine: a. Water content b. Void ratio c. Moist unit weight d. Dry unit weight f. Effective unit weight

A sample of dry sand having a unit weight of 16.00 kN/m³ and a specific gravity of 2.65 is placed in the rain. During the rain the volume of the sample remains constant but the degree of saturation increases to 45%. I. What is the water content after being in the rain, in percentage? What would be the mass of water, in kg, added to the soil due to exposure to rain (assume unit volume)?

Problem Set 2: 4. A sample of gray silty clay has a mass of 126 kg. Laboratory tests results give a moist density (p) of 2.05 g/cm³, a specific gravity of solids (G,) of 2.71, and a moisture content (w) of 15.7%. First determine all entries in the phase diagram. Then determine the void ratio (e), the porosity (n), the degree of saturation (S), the dry density (Pa), the dry unit weight (ya), and the moist unit weight (y). Draw the Phase diagram.

a. The moisture content of the soil specimen is 20%, and the total weight is 300 gr. Calculate the void ratio and degree of saturation if the total volume was 180 cm3. (Gs = 2.5) b. A soil layer with a moisture content of 10 percent and a unit weight of 16.5 KN per cubic meter has a decrease in volume by 10 percent after compaction. Find the dry specific weight of the soil.