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Name: ____________________ Date: ____________
1.Easy
A 10 m thick normally consolidated clay layer (γsat = 18.5 kN/m³, Cc = 0.15, e₀ = 0.6) lies below 3.5 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 140 kPa. Treat the layer as one sublayer with the stresses at its mid-depth. Find the primary consolidation settlement S in mm.
sand: Hs = 3.5 m, γ = 18.5 kN/m³clay: H = 10 m, γsat = 18.5 kN/m³γw = 9.81 kN/m³Cc = 0.15e0 = 0.6Δσ = 140 kPa
S = mm
2.Easy
A 5.5 m thick layer of normally consolidated clay (Cc = 0.25, e₀ = 1.1) has an effective vertical stress of 80 kPa at its mid-depth. A wide fill raises the vertical stress in the clay by 105 kPa. Treat the layer as one sublayer with the stresses at its mid-depth. Find the primary consolidation settlement S in mm.
A 2.5 m thick overconsolidated clay layer has Cc = 0.4, Cr = 0.03 and e₀ = 1.1. At its mid-depth the effective vertical stress is 50 kPa and the preconsolidation pressure is 80 kPa. A new building adds 50 kPa of vertical stress at mid-depth. Find the primary consolidation settlement S in mm.
A 3.5 m thick overconsolidated clay layer has Cc = 0.2, Cr = 0.06 and e₀ = 0.7. At its mid-depth the effective vertical stress is 45 kPa and the preconsolidation pressure is 115 kPa. A new building adds 220 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 = 0.8 m²/year. It lies on impervious rock, with sand above it, so water drains out only at the top. For 80% average consolidation the time factor is Tv = 0.567. How many years t does the layer take to reach 80% consolidation?
A clay layer 7 m thick has a coefficient of consolidation cv = 0.8 m²/year. It lies between two sand layers, so water drains out at the top and the bottom. For 80% average consolidation the time factor is Tv = 0.567. How many years t does the layer take to reach 80% consolidation?