Assume p = 1000 kg/m; %= 9.8 kN/m; g = 9.8 m/s for all questions in...

  

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Assume p = 1000 kg/m³; %= 9.8 kN/m³; g = 9.8 m²/s for all questions in this assignment. You have completed a drilling investigation for a site proposed for a proposed development for a new housing complex. The results of your investigation are given in Table 1 below: Table 1 Depth Below Ground 0.0 m-1.0 m 1.0 m-4.0 m Fractured bedrock Soil Description Very dense silty sand (previously compacted to max dry density) Clay Water Content 35 Sample Mass (g) 710.7 Sample Volume (cm³) 385 Encountered at 4 m Depth, Borehole Terminated Drilling Notes: water level in borehole was observed at a depth of 1.0 m below ground. You also ordered a consolidation test for the clay from a sample taken at a depth of 2.5 m below ground. The results from the consolidation test are shown in Table 2 below. You have also determined from consolidation testing the coefficient of consolidation, cv, is 0.05 m²/yr. Table 2 Effective Stress (kPa) 25 50 100 200 400 800 400 200 100 50 25 Void Ratio 0.93 0.924 0.91 0.85 0.793 0.736 0.742 0..748 0..754 0.760 0.766 As the engineer for this project, you are required to increase the grade of the site by 3m with engineered fill of the same soil that is present from 0.0-1.0m. The fill will be placed at 100% of its maximum dry density (1667 kg/m³) and its optimum water content (20%). For this project, your boss has asked you to: 1) calculate the settlement anticipated for the placement of the new 3m thickness of engineered fill. 2) Produce a plot that shows the consolidation settlement as it will develop over the next 10 years. This is the time it is anticipated it will be before any housing gets built in this area. 3) When will 50% of the consolidation settlement be complete? 90%? Any comments about this time relative to the anticipated 10 years mentioned above? State your assumptions used to solve this problem. For simplicity, assume a specific gravity of 2.65 for the clay. Assume p = 1000 kg/m³; %= 9.8 kN/m³; g = 9.8 m²/s for all questions in this assignment. You have completed a drilling investigation for a site proposed for a proposed development for a new housing complex. The results of your investigation are given in Table 1 below: Table 1 Depth Below Ground 0.0 m-1.0 m 1.0 m-4.0 m Fractured bedrock Soil Description Very dense silty sand (previously compacted to max dry density) Clay Water Content 35 Sample Mass (g) 710.7 Sample Volume (cm³) 385 Encountered at 4 m Depth, Borehole Terminated Drilling Notes: water level in borehole was observed at a depth of 1.0 m below ground. You also ordered a consolidation test for the clay from a sample taken at a depth of 2.5 m below ground. The results from the consolidation test are shown in Table 2 below. You have also determined from consolidation testing the coefficient of consolidation, cv, is 0.05 m²/yr. Table 2 Effective Stress (kPa) 25 50 100 200 400 800 400 200 100 50 25 Void Ratio 0.93 0.924 0.91 0.85 0.793 0.736 0.742 0..748 0..754 0.760 0.766 As the engineer for this project, you are required to increase the grade of the site by 3m with engineered fill of the same soil that is present from 0.0-1.0m. The fill will be placed at 100% of its maximum dry density (1667 kg/m³) and its optimum water content (20%). For this project, your boss has asked you to: 1) calculate the settlement anticipated for the placement of the new 3m thickness of engineered fill. 2) Produce a plot that shows the consolidation settlement as it will develop over the next 10 years. This is the time it is anticipated it will be before any housing gets built in this area. 3) When will 50% of the consolidation settlement be complete? 90%? Any comments about this time relative to the anticipated 10 years mentioned above? State your assumptions used to solve this problem. For simplicity, assume a specific gravity of 2.65 for the clay.