A 7.5 m thick layer of normally consolidated clay (Cc = 0.3, e₀ = 0.95) has an effective vertical stress of 110 kPa at its mid-depth. A wide fill raises the vertical stress in the clay by 115 kPa. Treat the layer as one sublayer with the stresses at its mid-depth. Find the primary consolidation settlement S in mm.
Consolidation settlement worksheet with answers
A 3.5 m thick layer of normally consolidated clay (Cc = 0.4, e₀ = 1) has an effective vertical stress of 85 kPa at its mid-depth. A wide fill raises the vertical stress in the clay by 55 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 = 0.5, Cr = 0.06 and e₀ = 0.6. At its mid-depth the effective vertical stress is 115 kPa and the preconsolidation pressure is 165 kPa. A new building adds 45 kPa of vertical stress at mid-depth. Find the primary consolidation settlement S in mm.
A 6.5 m thick overconsolidated clay layer has Cc = 0.4, Cr = 0.03 and e₀ = 0.65. At its mid-depth the effective vertical stress is 85 kPa and the preconsolidation pressure is 115 kPa. A new building adds 170 kPa of vertical stress at mid-depth. Find the primary consolidation settlement S in mm.
In a laboratory oedometer test, a clay specimen 25 mm thick, drained at the top and bottom, reaches 50% consolidation in 10 min. In the field the same clay forms a layer 8 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?
A clay layer 8 m thick has a coefficient of consolidation cv = 1 m²/year. It lies on impervious rock, with sand above it, so water drains out only at the top. For 50% average consolidation the time factor is Tv = 0.197. How many years t does the layer take to reach 50% consolidation?
Answer key
- 1. S = 358.6 mm
- 2. S = 151.7 mm
- 3. S = 13.45 mm
- 4. S = 560.5 mm
- 5. t = 2844 days
- 6. t = 12.61 years
Full step-by-step solutions: practise this topic on examproblems.com.