Consolidation settlement worksheet with answers

Free printable Consolidation settlement worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

For teachers: free to print, copy and use in class. Every new worksheet has new values and its own answer key. A link to ExamProblems on your course page is appreciated.

Name: ____________________   Date: ____________

1.Easy
Δσ = 80 kPasandclayCc​ = 0.6e0​ = 1σ′0​ = 85 kPa7.5 mwater table

A 7.5 m thick layer of normally consolidated clay (Cc = 0.6, 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 80 kPa. Treat the layer as one sublayer with the stresses at its mid-depth. Find the primary consolidation settlement S in mm.

H = 7.5 mCc = 0.6e0 = 1σ′0 = 85 kPaΔσ = 80 kPa
S = mm
2.Easy
Δσ = 30 kPasandclayCc​ = 0.6e0​ = 0.85σ′0​ = 45 kPa2 mwater table

A 2 m thick layer of normally consolidated clay (Cc = 0.6, e₀ = 0.85) has an effective vertical stress of 45 kPa at its mid-depth. A wide fill raises the vertical stress in the clay by 30 kPa. Treat the layer as one sublayer with the stresses at its mid-depth. Find the primary consolidation settlement S in mm.

H = 2 mCc = 0.6e0 = 0.85σ′0 = 45 kPaΔσ = 30 kPa
S = mm
3.Medium
Δσ = 90 kPasandclayCc​ = 0.25, Cr​ = 0.02e0​ = 1.15σ′0​ = 50 kPaσ′p​ = 120 kPa4.5 mwater table

A 4.5 m thick overconsolidated clay layer has Cc = 0.25, Cr = 0.02 and e₀ = 1.15. At its mid-depth the effective vertical stress is 50 kPa and the preconsolidation pressure is 120 kPa. A new building adds 90 kPa of vertical stress at mid-depth. Find the primary consolidation settlement S in mm.

H = 4.5 mCc = 0.25Cr = 0.02e0 = 1.15σ′0 = 50 kPaσ′p = 120 kPaΔσ = 90 kPa
S = mm
4.Medium
Δσ = 120 kPasandclayCc​ = 0.4, Cr​ = 0.06e0​ = 1.15σ′0​ = 105 kPaOCR = 33 mwater table

A 3 m thick overconsolidated clay layer has Cc = 0.4, Cr = 0.06 and e₀ = 1.15. At its mid-depth the effective vertical stress is 105 kPa and the overconsolidation ratio is OCR = 3. A new building adds 120 kPa of vertical stress at mid-depth. Find the primary consolidation settlement S in mm.

H = 3 mCc = 0.4Cr = 0.06e0 = 1.15σ′0 = 105 kPaOCR = 3Δσ = 120 kPa
S = mm
5.Hard
sandclayH = 2.5 m2.5 msandwater table

In a laboratory oedometer test, a clay specimen 25 mm thick, drained at the top and bottom, reaches 50% consolidation in 8 min. In the field the same clay forms a layer 2.5 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?

hlab = 25 mmtlab = 8 minH = 2.5 mfield: double drainage
t = days
6.Hard
sandclayH = 4.5 m4.5 msandwater table

In a laboratory oedometer test, a clay specimen 19 mm thick, drained at the top and bottom, reaches 50% consolidation in 5 min. In the field the same clay forms a layer 4.5 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?

hlab = 19 mmtlab = 5 minH = 4.5 mfield: double drainage
t = days

Answer key

  1. 1. S = 648.1 mm
  2. 2. S = 143.9 mm
  3. 3. S = 50.95 mm
  4. 4. S = 27.71 mm
  5. 5. t = 55.56 days
  6. 6. t = 194.8 days

Full step-by-step solutions: practise this topic on examproblems.com.