A 7 m thick layer of normally consolidated clay (Cc = 0.35, e₀ = 0.9) has an effective vertical stress of 75 kPa at its mid-depth. A wide fill raises the vertical stress in the clay by 125 kPa. Treat the layer as one sublayer with the stresses at its mid-depth. Find the primary consolidation settlement S in mm.
A 6 m thick normally consolidated clay layer (γsat = 19 kN/m³, Cc = 0.6, e₀ = 1.25) lies below 3 m of sand (γ = 18.5 kN/m³). The water table is at the top of the clay; use γw = 9.81 kN/m³. A wide fill raises the vertical stress throughout the clay by 70 kPa. Treat the layer as one sublayer with the stresses at its mid-depth. Find the primary consolidation settlement S in mm.
A 5.5 m thick overconsolidated clay layer has Cc = 0.25, Cr = 0.06 and e₀ = 1.1. At its mid-depth the effective vertical stress is 105 kPa and the preconsolidation pressure is 215 kPa. A new building adds 170 kPa of vertical stress at mid-depth. Find the primary consolidation settlement S in mm.
A 2.5 m thick overconsolidated clay layer has Cc = 0.3, Cr = 0.06 and e₀ = 0.7. At its mid-depth the effective vertical stress is 90 kPa and the preconsolidation pressure is 130 kPa. A new building adds 140 kPa of vertical stress at mid-depth. Find the primary consolidation settlement S in mm.
A clay layer 3 m thick has a coefficient of consolidation cv = 2 m²/year. It lies on impervious rock, with sand above it, so water drains out only at the top. For 70% average consolidation the time factor is Tv = 0.403. How many years t does the layer take to reach 70% consolidation?
In a laboratory oedometer test, a clay specimen 20 mm thick, drained at the top and bottom, reaches 50% consolidation in 15 min. In the field the same clay forms a layer 5 m thick. It lies between two sand layers, so water drains out at the top and the bottom. How many days t does the field layer take to reach 50% consolidation?
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