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MSETTLE USER MANUAL
The pre-consolidation process is set variable within the layer and corrected at every
step which writes:
(119)
Pc ;i = max (Pc ;i −1 ; σ i′−1 )
with
(for benchmarks a, b, e and f)
⎧σ p
⎪
(for benchmarks c and g)
Pc ;1 = ⎨OCR σ 0′
⎪ POP + σ ′ (for benchmarks d and h)
0
⎩
The phreatic/piezometric line is situated 20 mm above the layer.
Table 22-1 – Loading-steps (bm3-1)
Load-step i Application time ti
[days]
0
Initial state
1
0
2
1
3
2
4
3
5
4
6
5
7
6
8
7
Loading/Unloading Δσi
[kPa]
2
5
-5
5
5
-5
5
10
20
Cumulative load σi
[kPa]
Initial load
5
0
5
10
5
10
20
40
An initial load of 2 kPa and a layer thickness of only 20 mm permit to assume a
constant initial effective stress distribution along the layer (σ0’ = 0.28 kPa).
The calculation without consolidation yields the analytical solution given by:
• equations (59) to (62) page 305 [§ 16.3.1] for loading steps;
• equation (63) page 306 [§ 16.3.2] for unloading steps.
Settlement calculations are performed using both linear and natural strains. For
natural strain, equation (64) page 306 [§ 16.3.3] applies.
MSettle result
The settlements calculated by MSettle are exported to the spread sheet using the
View Data option in Time-History window for comparison (see figures below). The
settlements after 4 and 8 days are given in Table 22-2.