A uniform surcharge of 32kN/m² has been applied on the horizontal ground surface lying 8m above the top of a 4m thick, saturated clay layer. Above the clay is sand (Unit weight of sand%318kN/m), and below the clay (Unit weight of clay=20kN/m) lied impervious rock. The final consolidation settlement in the clay layer has been calculated as 24mm. The point P lies 1.0m below the top of the clay layer. The coefficient of consolidation of the clay is 1.6m2/year. (Remainder T=C,.t/d). Just write the answers, no need to show calculations. a) What is the degree of consolidation at point P, when the pore pressure at P is 68kPa? b) How many years are required for 50% average degree of consolidation in the clay layer, if the relevant time factor is 0.196.? C) What is the effective stress at the middle of the sand layer immediately after the application of surcharge, if the drained and saturated unit weights of the sand are 16kNm3 and 18kN/m3, respectively. d) What is the increase in effective stress at P immediately after the application of the surcharge.?

A uniform surcharge of 32kN/m² has been applied on the horizontal ground surface lying 8m above the top of a 4m thick, saturated clay layer. Above the clay is sand (Unit weight of sand%318kN/m), and below the clay (Unit weight of clay=20kN/m) lied impervious rock. The final consolidation settlement in the clay layer has been calculated as 24mm. The point P lies 1.0m below the top of the clay layer. The coefficient of consolidation of the clay is 1.6m2/year. (Remainder T=C,.t/d). Just write the answers, no need to show calculations. a) What is the degree of consolidation at point P, when the pore pressure at P is 68kPa? b) How many years are required for 50% average degree of consolidation in the clay layer, if the relevant time factor is 0.196.? C) What is the effective stress at the middle of the sand layer immediately after the application of surcharge, if the drained and saturated unit weights of the sand are 16kNm3 and 18kN/m3, respectively. d) What is the increase in effective stress at P immediately after the application of the surcharge.?

Fundamentals of Geotechnical Engineering (MindTap Course List)

5th Edition

ISBN:9781305635180

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter9: Consolidation

Section: Chapter Questions

Problem 9.17P

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