An 8 m thick layer of normally consolidated clay (Cc = 0.6, e₀ = 1.15) has an effective vertical stress of 65 kPa at its mid-depth. A wide fill raises the vertical stress in the clay by 20 kPa. Treat the layer as one sublayer with the stresses at its mid-depth. Find the primary consolidation settlement S in mm.
A 9 m thick normally consolidated clay layer (γsat = 17.5 kN/m³, Cc = 0.15, e₀ = 1.25) lies below 3.5 m of sand (γ = 17 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 35 kPa. Treat the layer as one sublayer with the stresses at its mid-depth. Find the primary consolidation settlement S in mm.
A 3 m thick overconsolidated clay layer has Cc = 0.45, Cr = 0.06 and e₀ = 0.85. At its mid-depth the effective vertical stress is 115 kPa and the preconsolidation pressure is 225 kPa. A new building adds 220 kPa of vertical stress at mid-depth. Find the primary consolidation settlement S in mm.
A 5.5 m thick overconsolidated clay layer has Cc = 0.5, Cr = 0.06 and e₀ = 1. At its mid-depth the effective vertical stress is 55 kPa and the preconsolidation pressure is 85 kPa. A new building adds 25 kPa of vertical stress at mid-depth. Find the primary consolidation settlement S in mm.
A clay layer 2.5 m thick has a coefficient of consolidation cv = 1.2 m²/year. It lies between two sand layers, so water drains out at the top and the bottom. For 50% average consolidation the time factor is Tv = 0.197. How many years t does the layer take to reach 50% consolidation?
In a laboratory oedometer test, a clay specimen 20 mm thick, drained at the top and bottom, reaches 50% consolidation in 12 min. In the field the same clay forms a layer 4.5 m thick. It lies on impervious rock, with sand above it, so water drains out only at the top. How many days t does the field layer take to reach 50% consolidation?
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