Ground engineering · Consolidation & preloading
Settlement monitoring: Asaoka and hyperbolic prediction calculator
Predicts the final settlement from settlement-plate readings at a constant interval by two independent methods, and the residual settlement still to come.
Standard: Asaoka (1978) · Tan (1971) hyperbolic method
Open the live calculator → All ground engineering calculators
Inputs in the worked example
The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.
| Input | Value | Unit |
|---|---|---|
| Allowable residual settlement after handover | 150 | mm |
| Readings: time (days), settlement (mm) — constant interval | 60, 102.2 120, 144.6 180, 176.8 240, 203.9 300, 228.7 360, 247.9 420, 267.0 480, 282.9 540, 296.9 600, 309.8 660, 319.4 |
Worked example — results
| Result | Value | Unit |
|---|---|---|
| Asaoka β1 | 0.855 | |
| Asaoka β0 | 54.46 | mm |
| Asaoka s∞ = β0/(1 − β1) | 376.0 | mm |
| Hyperbolic β (slope of t/s) | 0.002 | 1/mm |
| Hyperbolic α (intercept) | 0.559 | days/mm |
| Hyperbolic s∞ = 1/β | 425.1 | mm |
| Latest settlement | 319.4 | mm |
| Degree of consolidation (Asaoka) | 84.94 | % |
| Residual (larger estimate − latest) | 105.7 | mm |
- ✓ Residual settlement ≤ allowable
- ✓ Asaoka β1 < 1 (converging)
Method, formulas and assumptions
- Asaoka β1 = SLOPE([t.si],[t.sp]) = 0.85516
- Asaoka β0 = INTERCEPT([t.si],[t.sp]) = 54.464 mm
- Asaoka s∞ = β0/(1 − β1) = 54.464/(1-0.85516) = 376.03 mm
- Hyperbolic β (slope of t/s) = SLOPE([t.ts],[t.tt]) = 0.0023525 1/mm
- Hyperbolic α (intercept) = INTERCEPT([t.ts],[t.tt]) = 0.55925 days/mm
- Hyperbolic s∞ = 1/β = 1/0.0023525 = 425.08 mm
- Latest settlement = INDEX([t.s],COUNT([t.s])) = 319.4 mm
- Degree of consolidation (Asaoka) = 319.4/376.03*100 = 84.94 %
- Residual (larger estimate − latest) = MAX(376.03,425.08)-319.4 = 105.68 mm
- Use readings after the final fill or surcharge was placed. Early, pre-60 % data under-predict with both methods.
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For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.