A soil profile consists of a clay layer and two sand layers; the clay layer is “sandwiched” between two sand layers as s
Posted: Mon May 16, 2022 8:24 am
A soil profile consists of a clay layer and two sand layers; the
clay layer is “sandwiched” between two sand layers as shown below.
A surcharge of q = 120 kN/m2 is applied to the ground surface,
which causes an increase of total stress (Δσ) of approximately 120
kN/m2 in the clay layer from top to bottom. This loading in the
clay layer, in turn, causes a consolidation of the clay layer. The
coefficient of consolidation of the clay layer equals to 1.4 m2
/year.
Problem 6 (20 points): A soil profile consists of a clay layer and two sand layers; the clay layer is "sandwiched" between two sand layers as shown below. A surcharge of q = 120 kN/m2 is applied to the ground surface, which causes an increase of total stress (Ag) of approximately 120 kN/m2 in the clay layer from top to bottom. This loading in the clay layer, in turn, causes a consolidation of the clay layer. The coefficient of consolidation of the clay layer equals to 1.4 m² /year. Surcharge q H = 10 m Sand, ya = 16 kN/m * Groundwater table H =10 m Sand, Ysat = 17 kN/m H = 10 m Clay, Ysat = 19 kN/m Void ratio e Sand, Ysat = 17 kN/m Sand Clay
Answer the following questions: a) Before the surcharge is applied, what is the hydrostatic pore water pressure, up at the middle of the clay layer? What is the effective stress at the middle of the clay layer at this point? Hydrostatic pore water pressure, Jo = kPa (round to 2 decimal places) Effective stress at the middle of the clay layer = kPa b) Immediately after the surcharge is applied, what is the excess pore water pressure, Au, at the middle of the clay layer? What is the total pore water pressure at the middle of the clay layer at this point? The excess pore water pressure, Au = kPa kPa (round to 2 decimal Total pore water pressure at the middle of the clay layer = places) C) After the surcharge is applied, the consolidation of the clay layer begins. What is the excess pore water pressure, Au, at the middle of the clay layer at the end of consolidation? Excess pore water pressure, Au, at the middle of the clay layer at the end of consolidation = kPa d) What is the effective stress at the middle of the clay layer at the end of consolidation? Effective stress at the middle of the clay layer = kPa e) To reach 50% consolidation of the clay layer, it takes years. (round to 2 decimal places) f) The average degree of consolidation after 5 years = % (round to 1 decimal places)
clay layer is “sandwiched” between two sand layers as shown below.
A surcharge of q = 120 kN/m2 is applied to the ground surface,
which causes an increase of total stress (Δσ) of approximately 120
kN/m2 in the clay layer from top to bottom. This loading in the
clay layer, in turn, causes a consolidation of the clay layer. The
coefficient of consolidation of the clay layer equals to 1.4 m2
/year.
- A Soil Profile Consists Of A Clay Layer And Two Sand Layers The Clay Layer Is Sandwiched Between Two Sand Layers As S 1 (268.29 KiB) Viewed 57 times
- A Soil Profile Consists Of A Clay Layer And Two Sand Layers The Clay Layer Is Sandwiched Between Two Sand Layers As S 2 (57.26 KiB) Viewed 57 times
Answer the following questions: a) Before the surcharge is applied, what is the hydrostatic pore water pressure, up at the middle of the clay layer? What is the effective stress at the middle of the clay layer at this point? Hydrostatic pore water pressure, Jo = kPa (round to 2 decimal places) Effective stress at the middle of the clay layer = kPa b) Immediately after the surcharge is applied, what is the excess pore water pressure, Au, at the middle of the clay layer? What is the total pore water pressure at the middle of the clay layer at this point? The excess pore water pressure, Au = kPa kPa (round to 2 decimal Total pore water pressure at the middle of the clay layer = places) C) After the surcharge is applied, the consolidation of the clay layer begins. What is the excess pore water pressure, Au, at the middle of the clay layer at the end of consolidation? Excess pore water pressure, Au, at the middle of the clay layer at the end of consolidation = kPa d) What is the effective stress at the middle of the clay layer at the end of consolidation? Effective stress at the middle of the clay layer = kPa e) To reach 50% consolidation of the clay layer, it takes years. (round to 2 decimal places) f) The average degree of consolidation after 5 years = % (round to 1 decimal places)