Practical modeling of diaphragm walls and foundation rafts with piles part I

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1 Practical modeling of diaphragm walls and foundation rafts with piles part I

2 FE mesh This example concerns modeling of a deep excavation protected by concrete wall an then by a construction of foundation raft strengthened by bored piles. Foundation supports 11th storey building.

3 Horizontal cross section Diaphragm wall slab Dimension of the excavation is 90 m by 60 m in horizontal cross section.

4 Engineering draft 10 kn/m 2 Slabs thickness 30 cm 1 st stage 3.5 m 2 nd stage 3 rd stage 4 th stage -5 m 3.5 m 3.5 m 3.5 m 1.0 m m plate 13.0 m Diaphragm wall Excavation is protected by 0.8 m thick concrete wall and will be performed in four steps up to level m. Ground water table is at level -5.0 m. One meter thick plate is strengthen by ten meters long bored piles. Outside the excavation surface load of magnitude 10 kn/m2 is applied.

5 Model components Nodal links connection of nonconforming meshes Continuum 3D Piles Interface elements between diaphragm walls and soil shells

6 Box shaped solid boundary conditions and pressure boundary conditions for deformation and flow analysis have to be defined. Boundary conditions Pressure boundary conditions Solid boundary conditions Pressure head Seepage elements

7 Loads Surface load 10 kn/m 2 Nodal loads Surface load outside of excavation zone is applied to the soil and surface. Nodal loads are applied to foundation plate.

Model definition strategy internal.inp external.inp slabs.inp In order to simplify model generation, model will be defined in three parts: external, internal and building.

8 Model definition strategy internal.inp external.inp slabs.inp In order to simplify model generation, model will be defined in three parts: external, internal and building. External part contains soil close to model boundary with coarse mesh in order to decrease number of degrees of freedom in the analysis. Internal part contains excavation zone with diaphragm walls and foundation plate. Building with shells and beams will defined in third part. All parts will merged into one model.

9 Run ZSoil 1. In Preselection screen select : - Analysis type: 3D - Problem type: Deformation + Flow Project preselection dialog box appears automatically when Zsoil Menu is started or for option File/New. Preselection can be changed in ZSoil Menu or/and in ZSoil Preprocessor:

10 Import data settings Definition of the material properties, load and existence functions and drivers will be skipped in this tutorial. All these settings will be imported from INP file.

11 Existence functions The sequence of excavation/construction stages is controlled by the existence functions, which are defined according to the sequence of events specified in the table below. Construction stage Time Action Initial state 0 Wall installation 1 Wall and interface on the wall 1 st excavation 10 excavation up to level -3.5 m Seepage on the level 0.0 m has to be removed Seepage on the level -3.5 m has to be defined 1 st slab 30 Slab at the level -3.5 has to be defined 2 nd excavation 30 excavation up to level -7.0 m Seepage on the level -3.5 m has to be removed Seepage on the level -7.0 m has to be defined 2 nd slab 50 Slab at the level -7.0 has to be defined 3 rd excavation 50 excavation up to level m Seepage on the level -7.0 m has to be removed Seepage on the level m has to be defined

12 Existence functions Construction stage Time Action 3 rd slab 70 Slab at the level has to be defined 4 th excavation 70 excavation up to level -15 m Seepage on the level m has to be removed Seepage on the level m has to be defined Piles 75 Plate 80

13 Click on this button to display next selected existence functions Click on the column in order to select all existence functions Selected existence functions are displayed on the plot

14 Click on this button to return to previously displayed existence functions Existence functions

15 Load functions The load time function associated with the surface load

16 Load functions The load time function associated with unloading of all excavation zones

17 Materials

$Under ZSoil Menu choose File\Save As 1. Save as Internal.inp 2. Save as slabs.inp 3. Save as external.$

18 Saving files for all parts Imported data (materials, drivers, existence and load functions) will be used during geometry definition of all parts of the model. Let save current stage into 3 files. Under ZSoil Menu choose File\Save As 1. Save as Internal.inp 2. Save as slabs.inp 3. Save as external.inp 4. Run Preprocessing Last saved file is external.inp so data for this part of the model will generated in the Preprocessing.

19 Definition of external part - overview 1. Lines 2. Continuum 2D subdomain with virtual mesh 3. Extrude 2D subdomains to 3D subdomains 4. Delete one internal subdomain

Definition of external part Create construction lines -80-45 -95-60 60 95 45 80 To speedup drawing of the

20 Definition of external part Create construction lines To speedup drawing of the model (especially in 3D) create construction lines using the toolbar, or top menu Settings/Construction lines.

Create construction lines Delete all (clik on

Delete all Add characteristic Y coordinate: 0

21 Create construction lines Delete all (clik on position column in order to select all elements and press Delete button) Add characteristic X coordinates: -95, -60, 60, 9, Delete all Add characteristic Y coordinate: 0 Delete all Add characteristic Z coordinates: -80, -45, 45, 80

22 Create two rectangles 1. Draw an external rectangle 2. Draw an internal rectangle

23 Create lines 3. Turn off Continue 4. Draw four remaining segments lines connecting external rectangle with internal one

24 Create Continuum 2D inside contour 1. Set XZ projection 2D continuum subdomains will be created through method 2D continuum in contour by picking the point within the closed contour. It is important to set proper project to avoid ambiguity during picking internal point.

$Macro Model\Subdomain\ 2D Continuum inside contour 3.$

25 Create Continuum 2D inside contour 2. Macro Model\Subdomain\ 2D Continuum inside contour 3. Pick 5 times to create 5 subdomains

$Macro Model\Subdomain\ Create virtual mesh$ 2. Pick internal Subdomain 3.

26 Create virtual mesh 1. Macro Model\Subdomain\ Create virtual mesh 2. Pick internal Subdomain 3. Set Split 10 for Edge 1-2 and for edge Press button Create virtual mesh!

27 Create virtual mesh 5. Pick one of external Subdomain 6. Set Split for Edge 1-4, split for edge 1-2 will be inherited from internal subdomian, which defines split for common edge 7. Press button Create virtual mesh Split for this edge is defined by split adjustment to existing meshed Subdomains

28 Create virtual mesh 8. Pick next external Subdomain 9. Press button Create virtual mesh 10.Repeat steps for next two ramaining subdomains Split for both edges is defined by split adjustment to existing meshed Subdomains

29 Create Continuum 3D by faces extrusion 1. Set 3D view 2. Select faces in zoom box

30 Create Continuum 3D by faces extrusion 3. Macro Model\Subdomain\ 3D Continuum\ 3D Continuum by Face(s) extrusion

31 Create Continuum 3D by faces extrusion 4. Set vector 6. Define parameters for multiple extrusion and press OK 7. Apply 5. Check multiple extrusion

32 Delete Continuum 2D subdomains 1. Hide Continuum 3D subdomains 2. CTRL-A select all 3. Delete from menu SUBDOMAIN => Continuum 2D subdomains will be deleted 4. Show Continuum 3D subdomains

33 Remove top Continuum 3D subdomain 1. Macro Model\Subdomain\ Delete or icon Delete 2. Pick Subdomain

34 Definition of Seepage elements 1. Set orthogonal cameraortogonalną 2. Set XY view 3. Set cursor in Select faces in zoom box mode 4. Select top faces 5. Macro Model\ Seepage\On Subdomain face(s)

35 Seepage 1. Unselect all 2. Set XZ view 3. Set cursor in Select faces in zoom box mode 4. Select external faces (4 x zoom box) 5. Macro Model\ Seepage\On Subdomain face(s)

36 Pressure BC 1. Macro Model\ Pressure BC\Fluid head on selected faces

37 Definition of external part is completed FILE\Save model and return to Main Menu Ignore warnings and exit application Save file in ZSoil menu =>File/Save

38 Definition of internal part In ZSoil menu Open Internal.inp Run Preprocessing Create construction lines

39 Create construction lines Delete all Add characteristic X coordinates: -60, -45, 45, 60 Delete all Add characteristic Y coordinate: 0 Delete all Add characteristic Z coordinates: -45, -30, 30, 45,

40 Create rectangles Draw 3 rectangles

$Macro Model\Subdomain\ 2D Continuum inside contour 3.$

41 Create Continuum 2D inside contour 1. Set XZ projection 2. Macro Model\Subdomain\ 2D Continuum inside contour 3. Pick 9 times to create 9 subdomains

$Create virtual mesh 1. Macro Model\Subdomain\ Create virtual mesh 2.$

42 Create virtual mesh 1. Macro Model\Subdomain\ Create virtual mesh 2. Pick internal Subdomain 3. Set Split 30 for Edge 1-2 and Press button Create virtual mesh

43 Create virtual mesh 5. Select corner SubdomainSubdomenę 6. Set split 6 for both edges 7. Create virtual mesh

44 Create virtual mesh Split 6 Split 6 Split 36 Split 6 Split 24 Split 6

45 Create Continuum 3D by faces extrusion 1. Set 3D view 2. Select faces in zoom box

46 Create Continuum 3D by faces extrusion 3. Macro Model\Subdomain\ 3D Continuum\ 3D Continuum by Face(s) extrusion

47 Create Continuum 3D by faces extrusion 4. Set vector 6. Define parameters for multiple extrusion and press OK 7. Apply 5. Check multiple extrusion

48 Delete Continuum 2D subdomains 1. Hide Continuum 3D subdomains 2. CTRL-A select all 3. Delete from menu SUBDOMAIN => Continuum 2D subdomains will be deleted 4. Show Continuum 3D subdomains

49 Setting parameters for excavated elements 1. Change to display Existence Function distribution 2. Define existence function and unloading function Macro Model\Subdomain\ Parameters

50 Setting parameters for excavated elements 1. Set cursor mode to Standard selection mode 2. Pick top internal subdomain 3. Hide selected elements Top subdomain has to be hidden in order to have acces to subdomain below

51 Setting parameters for excavated elements 1. Define existence function and unloading function Macro Model\Subdomain\ Parameters

52 Setting parameters for excavated elements 1. Set cursor mode to Standard selection mode 2. Pick top internal subdomain 3. Hide selected elements Top subdomain has to be hidden in order to have acces to subdomain below

53 Setting parameters for excavated elements 1. Define existence function and unloading function Macro Model\Subdomain\ Parameters

54 Setting parameters for excavated elements 1. Set cursor mode to Standard selection mode 2. Pick top internal subdomain 3. Hide selected elements

55 Setting parameters for excavated elements 1. Define existence function and unloading function Macro Model\Subdomain\ Parameters

56 Definition of the plate 1. Set cursor mode to Standard selection mode 2. Pick second internal subdomain 3. Hide selected elements

57 Plate 1. Macro Model\Subdomain\ 3D shell\3d shell on face(s)

58 Definition of the diaphragm wall These subdomains should be hidden Foundation plate 14 m 1 m Current state of the model Continuum 3D subdomain Model after hidding subdomains Definition of subdomains for diaphragm walls requires hidding foundation plate and continuum 3D subdomain below the plate

59 Definition of the diaphragm wall 1. Set cursor mode to Standard selection mode 2. Pick shell element 3. Hide selected elements 4. Pick 3rd subdomain 5. Hide selected elements

60 Definition of the diaphragm wall 1. Set cursor mode to Select faces with mouse mode 2. Select faces 3. Select Viewing mode to change camera orientation 4. Return to Select faces with mouse mode 5. Select faces

61 Definition of the diaphragm wall 3. Macro Model\Subdomain\ 3D shell\3d shell on face(s)

62 Definition of Interface elements on the wall 1. Open dialog box for Subdomain selection 4. Select elements 3. Replace selection 2. Select material number 5 (wall) 5. Close dialog box

63 Show selected element Macro Model\Interface\On Structural Subdomain(s)

64 Positive side => side with external normal Internal Interface is on positive side in this case

65 Why is it worth to define different material number for external and internal interface elements?

POSTPROCESSING Maps in postprocessing for interface

66 Why is it worth to define different material number for external and internal interface elements - POSTPROCESSING Maps in postprocessing for interface elements are overlapped. MAP FOR INTERFACE ELEMENTS MAPS ARE OVERLAPPED

67 Select elements with material number 20 With material number required interface element can be selected easily

68 Once selected elements are hidden map is displayed for one layer of elements

69 Definition of Seepage elements 1. Restore hidden elemens 2. Set cursor mode to Standard selection mode 3. Select top external faces 4. Macro Model\ Seepage\On Subdomain face(s)

$Macro Model\ Seepage\On Subdomain face(s) 7.$

70 Definition of Seepage elements 5. Unselect all faces 6. Macro Model\ Seepage\On Subdomain face(s) 7. Pick top face

71 Definition of Seepage elements under first excavated layer 1. Set cursor mode to Standard selection mode 2. Pick top subdomain 4. Hide selected elements 3. Pick top subdomain 4. Hide selected elements

72 Seepage first stage 1. Macro Model\ Seepage\On Subdomain face(s) 2. Pick top subdomain

Pick top seepage element 4. Hide selected elements 5.

73 Seepage second stage 1. Hide interface elements 2. Set cursor mode to Standard selection mode 3. Pick top seepage element 4. Hide selected elements 5. Pick top subdomain 6. Hide selected elements 7. Macro Model\Seepage\On Subdomain face(s) 8. Pick top face

74 Seepage third stage 1. Set cursor mode to Standard selection mode 2. Pick top seepage element 3. Hide selected elements 4. Pick top subdomain 5. Hide selected elements 6. Macro Model\Seepage\On Subdomain face(s) 7. Pick top face

$Pick top subdomain 5. Hide selected elements 6. Hide shells 7. Macro Model\ Seepage\On Subdomain face(s) 7. Pick top face$

75 Seepage 4 th stage 1. Set cursor mode to Standard selection mode 2. Pick top seepage element 3. Hide selected elements 4. Pick top subdomain 5. Hide selected elements 6. Hide shells 7. Macro Model\ Seepage\On Subdomain face(s) 7. Pick top face

$Check excavation stages Definition of internal part is completed FILE\Save model and return to$

76 Check excavation stages Definition of internal part is completed FILE\Save model and return to Main Menu with saving changes Ignore warnings and exit application Save file in ZSoil menu =>File/Save

77 Practical modeling of diaphragm walls and foundation rafts with piles part II

78 Slabs In ZSoil menu Open slabs.inp Run Preprocessing Create construction lines

79 1. Draw two rectangles 2. Draw 4 lines 3. Set XZ view 4. Set REPLACE selection mode 5. Set selection in Zoom box 6. Select 4 lines 6. Macro Model\Subdomain\Shell\3D Shell On Contour

80 1. Select 4 lines 2. Macro Model\Subdomain\Shell\3D Shell On Contour

$Model\Subdomain\Reverse$

81 Create virtual mesh split 4 split 36 split 24 split Set 3D view 2. Change direction for shell (if necessary) Macro Model\Subdomain\Reverse direction split 36

82 Parameters 1. Set selection in Zoom box 2. Select all shells 3. Macro Model\Subdomain\Parameters

$Model\Beam\Enter XYZ$ for 2 points 4.

83 1. Unselect all 2. Hide shell subdomains 3. Create beam FE Model\Beam\Enter XYZ for 2 points 4. Set parameters for beam FE Model\Beam\Parameters

84 1. Copy beam with translation FE Model\Beam\ Copy with translation

$Copy selected beams FE Model\Beam\Copy with translation 5.$

85 1. Set orthogonal camera 2. Set XZ view 3. Select beams in zoom box 4. Copy selected beams FE Model\Beam\Copy with translation 5. Unselect all

86 1. Change view 2. Move beam FE Model\Beam\Move 1. Change view 2. Move beam FE Model\Beam\Move

$FE Model\Beam\Copy by$

87 1. Select all Beams 2. Create auxiliary plane 2. Copy beam by symmetry 3. FE Model\Beam\Copy by symmetry

88 1. Unselect all 2. Set cursor in Standard selection mode 3. Select two beams 4. Copy selected beams FE Model\Beam\Copy with translation

89 1. Set XZ view 2. Set REPLACE selection mode 3. Set selection in Zoom box mode 4. Select one row of beams on left side 5. Copy selected beams FE Model\Beam\Copy with translation

90 1. Set selection in Zoom box mode 2. Select one row of beams on right side 3. Copy selected beams Model\Beam\Copy with translation

91 Copy columns and slabs 1. Show shell subdomains 2. Select all beams 3. Select all subdomains 4. Copy selected elements

92 Columns extension by 1 m up to level -15 m 1. Set orthogonal camera 2. Set XY view 3. Unselect all elements 4. Set selection in Zoom box mode 5. Select nodes in zoom box

93 Columns extension by 1 m up to level -15 m 1. FE Model\Node\Move

94 Set existence function for the slabs 1. Set Replace selection mode 2. Set selection in Zoom box 3. Select top slab 4. Macro ModeSubdomain\Parameters

$Macro ModeSubdomain\Parameters 3. Select third slab 4.$

95 Set existence function for the slabs 1. Select second slab 2. Macro ModeSubdomain\Parameters 3. Select third slab 4. Macro ModeSubdomain\Parameters

96 Piles under temporary columns 1. Creat lines by selected NODES extrusion Macro Model\Objects\Line\By Node(s) extrusion

97 Piles under building Set XZ view

$Model\Point\Point 2.$ $Model\Point\Copy$

98 Piles under building 1. Create point: Macro Model\Point\Point 2. Copy point: Macro Model\Point\Copy \Copy with translation

$Model\Point\Copy \Copy with$

99 Piles under building 1. Select points in Zoom Box 2. Copy points: Macro Model\Point\Copy \Copy with translation

$Model\Objects\Line\By$

100 Piles under building 1. Select points in Zoom Box 2. Creat lines by selected POINTS extrusion: Macro Model\Objects\Line\By Point(s) extrusion

101 Piles on selected objects 1. Set orthogonal camera 2. Set XY view 3. Unselect all elements 4. Set selection in Zoom box 5. Select lines dragging from rigth to left

102 Piles on selected objects 1. Macro Model\Pile\On object(s)

103 Set parameters for piles under building Set XZ view 1. Select elements in Zoom box 2. Macro Model\Pile\Parameters

$Model\Subdomain\Vistrual->Real$

104 Create real mesh 1. CTRL-A 2. Macro Model\Subdomain\Vistrual->Real mesh 3. Unselect all 4. Set 3D view 5. Hide local bases for shells

105 Linking columns with slabs 1. Select all beams 2. Select all nodes which belong to beams 3. Select all shells one layer

106 Linking columns with slabs 1. Show selected elements 2. Set XY view 3. Unselet all elements 4. Set selection in Zoom box mode

107 Linking columns with slabs 1. Select top nodes and shells 2. FE Model\Nodal link On node(s) 3. Unselet all elements

108 Linking columns with slabs 1. Set selection in Zoom box and select next nodes and shells 2. FE Model\Nodal link On node(s) 3. Unselet all elements

109 Linking columns with slabs 1. Set selection in Zoom box and select next nodes and shells 2. FE Model\Nodal link On node(s) 3. Unselet all elements

110 Check construction stages 1. Set 3D view 2. Set Show excavation/construction stages mode Save model and return Main Menu

$inp 3. Run preprocessing 4. File\Import geometrical model (*.inp) internal.$

111 Merging defined parts 1. Open External.inp in Zsoil Menu 2. Save as Wall3D.inp 3. Run preprocessing 4. File\Import geometrical model (*.inp) internal.inp

112 Surface load definition 1. Hide seepage 2. Select subdomain Faces 3. Macro Model\Surface Load\On Face(s) (Uniform)

113 Create Real mesh Select All (CTRL-A) Macro Model\Subdomain\Virtual -> Real mesh Hide objects 4. Unselect all

114 Create Nodal links 1. Select nodes with Inconsisten split

$Model\Continnum 3D\In zoom box SELECTION BY$

115 Create Nodal links 1. Set orthogonal camera 2. Set XZ view 3. Select Continuum 3D in zoom box : FE Model\Continnum 3D\In zoom box SELECTION BY ZOOM BOX FROM RIGHT TO LEFT (CROSSING)

116 Create Nodal links 1. Set XY view 2. Select Continuum 3D in zoom box : 3. Select Nodes from selected elements BRICK (B8) subtract from selection

$Model\$ $link\ On$

117 Create Nodal links FE Model\Nodal link\ On node(s) Unselect all

118 Merging step 2 File\Import geometrical model (*.inp) -> slabs.inp

119 Link Pile Head 1. Unselect all 2. Select shells with material Select all piles 4. Select all beams 5. Show selected elements

$Model\Piles\$

120 Link Pile Head 6. Macro Model\Piles\ Link Pile head

$Import nodal loads from external file FE Model\Loads\Noda load\import 0-15 10 0.15-1970.$

121 Import nodal loads from external file FE Model\Loads\Noda load\import

122 Link nodes with nodal load with plate 1. Show hidden nodes 2. Select nodes with nodal load

123 Link nodes with nodal load with plate FE Model\Nodal link\ On node(s)

124 Create boreholes Domain\Boreholes\From dialog 1. Press New 2. Enter Label 3. Enter coordinates 4. Enter data for layers 5. Press Add

125 Borehole 2 1. Press New 2. Enter Label 3. Enter coordinates 4. Enter data for layers 5. Press Add

126 Borehole 3 1. Press New 2. Enter Label 3. Enter coordinates 4. Enter data for layers 5. Press Add

127 Borehole 3 1. Enter data 2. Close dialog box

$Domain\Boreholes\Map material on visible elements Select$ material mapping can be checked by selection Continuum 3D

128 Domain\Boreholes\Map material on visible elements Select and show Continuum 3D elements with material 1 Results of material mapping can be checked by selection Continuum 3D elements with Initial material and displaying selected elements

129 Initial stresses FE Model\Initial Conditions\Initial stresses\on bounding box

130 Initial stresses

131 Solid BC FE Model\Boundary Conditions\Solid BC On box FILE\Save model and return to Main Menu with saving changes

$FE Model\Interface\Link Interface$

132 Linking bottom part of the wall with soil 1. Click line in order to select nodes 2. Press Return to the application 3. FE Model\Interface\Link Interface node(s) Check excavation stages FILE\Save model and return to Main Menu

133 Drivers c v E 2 oed k m d = = γ F kn m h t γ c = = 0.26 [ d] θc v 10 kn 3 m = m d 2

134 Two phase stabilization

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