A project end to end

This page uses eight members of the SlipSurface IQ family, one after another, on an imaginary port expansion site. Every step was actually run with the program's own starter project (or a small change to it), and the output is quoted as it came.

About the numbers

Each step uses its own program's starter example; the soil profiles are not identical from step to step. The aim is not to finish one design but to show how the right tool answers the right question.

Office building footings — SlipSurface IQ Bearing

A 2.5 × 4.0 m pad footing on layered ground (fill / stiff clay / dense sand); V = 1700 kN, H = 150 kN, M = 300 kNm.

slipsurface-bearing example -o office.bearing
slipsurface-bearing run office.bearing

Checks
  Bearing: FS = 2.96 ≥ 3.00 — NOT OK
  Sliding: FS = 5.33 ≥ 1.50 — OK
  Eccentricity: e/B = 0.071 ≤ 0.167 — OK

  The bearing check is satisfied from B = 2.51 m

Vesić gives q_ult = 533.5 kPa; Meyerhof is the most conservative (466.0 kPa). Decision: B = 2.60 m. → Bearing examples

Preload fill for the warehouse yard — SlipSurface IQ Settle

A 4 m high preload fill with a 12 m crest on soft clay:

values = forms.defaults()
values.update(shape="embankment", emb_crest=12.0, emb_height=4.0, emb_gamma=20.0)
r = Session(lang="en").analyse(values)

s = 228.0 mm · t90 = 5.1 years · Settlement check: NOT OK
center   total =  228.0 mm
shoulder total =  190.6 mm
midslope total =  108.5 mm
toe      total =   17.0 mm

90 % of the settlement takes 5.1 years — too long for a preload. Vertical drains will clearly be needed. → Settle examples

Stability of the fill — SlipSurface IQ LE

A 6 m fill on the same kind of soft clay (s_u = 12 + 1.8·z kPa), raised in one lift:

one lift, 6 m, su0 = 12 kPa : FS = 0.896
stage 1,  3 m, su0 = 12 kPa : FS = 1.362
stage 2,  6 m, su0 = 24 kPa : FS = 1.366

In one lift the fill fails (Bishop 0.896). Built in two stages, once consolidation under the first has raised s_u0 to 24 kPa, the second is safe at 1.37. Settle's t90 is the measure of that wait. → LE examples

Warehouse piled foundation — SlipSurface IQ Pile

A 3 × 3 group of bored piles, D = 0.80 m, L = 20 m, Q = 10 000 kN:

CHECKS
  Single pile: FS = 4.31 (required 2.50) — OK
  Group: FS = 3.10 (required 2.50) — OK
  Settlement: 32.8 mm (allowed 40.0 mm) — OK

  Required length: L = 18.50 m (tip at 20.00 m)

A length sweep shows an interesting detail: at L = 18 m the FS is only 1.84; as soon as the tip enters the dense sand (L = 20 m) it jumps to 4.31. Founding the piles in the dense sand is what matters. → Pile examples

Quay wall — SlipSurface IQ SPWA

An 8 m retained height, an NZ 26 sheet pile quay with two rows of anchors; k_h = 0.1:

Theoretical Required Embedment (D_req): 4.64 m
Design Embedment Depth (D_design):     6.00 m
...
Max. Absolute Moment: 564.58 kNm/m   (LE: 559.61)
Max. Deflection: 73.3 mm   (LE: 51.5)
STATUS: NOT OK - DEFLECTION EXCEEDED!

Limit equilibrium says the wall is adequate; the staged beam-spring analysis shows the deflection exceeding the H/120 = 66.7 mm limit. That is exactly the value of putting the two side by side: a stiffer section or prestressed anchors are needed. → SPWA examples

Pumping station deep excavation — SlipSurface IQ 2D

An 8 m excavation behind a bored pile wall (D1000 @ 1.2 m) with two rows of prestressed anchors; six stages:

stage 5/6: 5 - stress anchor row 2, excavate to 22.0 m
stage 6/6: 6 - factor of safety
lowest factor of safety: 2.034

Factor of safety (SSR)2.03

Wall max. moment219 kNm/m

Wall max. deflection20.8 mm

Anchor loads306 / 450 kN

→ 2D examples

Access ramp — SlipSurface IQ MSEW

A 6 m MSE wall with 50×4 steel strips:

External stability (FS)       value   required
  Sliding                      2.99      1.50   OK
  Overturning                  6.02      2.00   OK
  Bearing capacity             7.51      2.50   OK
Internal stability
  Pullout                      1.62      1.50   OK   (z = 5.625 m)
  Required uniform length: L = 5.13 m (FHWA minimum 4.20 m)

Pullout of the top layer governs — that is where the overburden is smallest. → MSEW examples

Fill quarry — SlipSurface IQ Kinematic

Six joint sets are screened against a 20 m rock face in the quarry:

Planar Sliding: 1 / 6
  E3               CRITICAL

The critical set goes to limit equilibrium: planar sliding with a tension crack, FS = 0.891. For FS = 1.5 the support required, at Hoek & Bray's optimum angle, is 697 kN/m. → Kinematic examples

Summary

Structure	Tool	Result	Decision
Office footing	Bearing	FS = 2.96 < 3.00	B = 2.60 m
Preload fill	Settle	228 mm, t90 = 5.1 years	Vertical drains
Fill stability	LE	0.90 → 1.36 / 1.37	Two-stage construction
Warehouse piles	Pile	FS 4.31 / group 3.10	L ≥ 18.5 m
Quay wall	SPWA	δ = 73 mm > 67 mm	Stiffer section
Deep excavation	2D	SSR = 2.03	Adequate
Access ramp	MSEW	Every check OK	L ≥ 5.13 m
Quarry face	Kinematic	FS = 0.89	697 kN/m of bolting

Each step's project file comes from the example command and re-runs with run; every number on this page can be reproduced on your own machine.