gts nx interfaces autocad midas gen for...

GTS NX

Integrated Solver Optimized for the next generation 64-bit platform

Finite Element Solutions for Geotechnical Engineering

GTS NX INTERFACES AUTOCAD – MIDAS

GEN FOR TUNNEL–SOIL–PILE

INTERACTION ANALYSIS

Angel F. Martinez

Civil Engineer

MIDASOFT

GTS NX

• This tutorial identifies the soil–

structure interaction by analyzing

construction stage of 3D tunnel

excavation and comparing differential

settlement of adjacent building.

• Part 1: 3D Terrain Generation

How to import DXF files and excel ta

bles to make accurate 3D terrain.

Part 2: Tunnel Collapse Analysis

Import 3D solid tunnel and loads for

tunnel failure analysis.

•Part 3: Soil–Pile–Tunnel Interaction

Import MXT files of a building from

midas GEN to analyze the differential

settlement during the excavation of a

tunnel.

Procedure

Excel

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Training Course Part 1

Import Topographic DXF file and combine with bore hole strata information

3D Terrain Generation

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1. Set coordinates to origin (0,0,0)

2. All Polylines3. Save as DXF

Export DXF from AUTOCAD

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Import Terrain DXF

1. Set model to 3D2. Import DXF 3D3. Select Boring

DXF file

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Import Strata Data

1. Geometry > Bedding Plane2. Import Excel data3. Set dimensions X:200

Y:200

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Import Topography

1. Import DXF file2. Select all layers3. Select all contours, set Zone4. Export .tms file

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Create 3D Terrain Geometry

1. Import terrain .tms file2. Create 3D box3. Divide box by 2D planes

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Training Course

Export 3D Terrain to AUTOCAD

1. Export CAD file as Parasolid2. Import to Autocad for modification3. Export CAD after changes

GTS NXTraining Course Part 2

Tunnel Collapse Analysis

GTS NXImport tunnel CAD

1. Options > Import > Unit > mm2. Import SAT file3. Measure dimensions

GTS NXImport terrain CAD

1. Options > Import > Unit > m 2. Import X_T file3. Check tunnel and terrain

GTS NXMove Tunnel CAD

1. Geometry Translate2. Move tunnel 30 m down3. Preview. Apply

GTS NXCreate 2D face

1. Move Work Plane2. Select 3 points of left face3. Draw Face over tunnel

GTS NXCopy 2D face

1. Geometry > Translate2. Copy face to opposite

parallel face of terrain3. Preview. Apply

GTS NXDivide tunnel by faces

1. Geometry > Divide > Solid2. Divide tunnel by 2 faces3. Delete extra tunnel sections

GTS NXConnect geometries

1. Geometry > Surface & Solid > Auto Connect2. Method Boolean > Select All3. Geometry > Tools > Check Duplicates

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Import Materials

1. Import Property from part 2 file

2. Inspect MaterialsTunnel Concrete Max Yield Stress 7500kN/m^2

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Mesh structures

1. Mesh > Generate > 3D2. Mesh Raft

Size: 5m Property: Concrete3. Mesh Tunnel

Size: 1m Property: Concrete

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Mesh soil layers

1. Mesh Top Soil LayerSize: 10m Property: Top Soil

2. Mesh 2nd Soil LayerSize: 10m Property: Mid Soil

3. Mesh 3rd Soil LayerSize: 10m Property: Bot Soil

4. Mesh 4th Soil LayerSize: 10m Property: Soft Rock

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Apply boundary

1. Static / Slope Analysis > Boundary > Constraint

2. Auto > Apply

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Import building loads from excel

1. Static / Slope Analysis > Load

2. Apply Gravity3. Import point loads

from excel table

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Create Analysis Case

1. Analysis Case > General

2. Type: Nonlinear static

Activate all except excavations3. Analysis Control > Activate options as shown

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Inspect results

1. Results > Displacement > Total Translation

Use Clipping Plane2. Deactivate all sets except tunnels

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Inspect results

1. Results > Solid Stresses > S- Von Mises

Shows Critical State of Tunnel Walls (Yield Stresses)

2. Results > Solid Stresses > Plastic Status

Shows material that had plastic failure

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Soil – Pile – Tunnel Interaction

Training Course Part 3

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Import building from midas GEN

1. Export structure from MIDAS Gen (MXT text file).2. Import building into GTS NX

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Import terrain geometry

1. Import CAD of terrain

2. Use imprint command on building footing for mesh connection with raft.

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Import materials

1. Import Property from GTS NX Steel Structure with soil and tunnel final

2. Inspect Materials

GTS NXMesh structures

1. Mesh > Generate > 3D2. Mesh raft

Size: 10m Property: Raft

3. Mesh Tunnel ExcavationsSize: 5m Property Mid Soil

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Mesh soil layers

1. Mesh Top Soil LayerSize: 10m Property: Top Soil

2. Mesh 2nd Soil LayerSize: 10m Property: Mid Soil

3. Mesh 3rd Soil LayerSize: 10m Property: Bot Soil

4. Mesh 4th Soil LayerSize: 10m Property: Soft Rock

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Extract tunnel walls

1. Mesh > Element > Extract

2. Select Tunnel Excavation geometriesActivate: Skip Duplicate Faces

Register Based on Owner

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Mesh piles

1. Mesh > Generate > 1D > Pile

2. Mesh > Element > Pile Interface &Pile Tip

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Apply boundary conditions

1. Static / Slope Analysis > Boundary > Constraint >Auto > Apply

2. Advance > RzRestrict rotation in Z axis of piles for stability

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Create Construction Stages

1. Static / Slope Analysis > Construction Stage > Stage Set

2. Stress > Add > Define CS

3. Stage 1: InitialActivate only Soil Layers, gravity and BC- Clear Displacements

Save > New

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Create Construction Stages

1. Stage 2: FoundationActivate foundation and building sets and BCSave > New

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Create Construction Stages

1. Stage 3: Exca 1Deactivate Tunnel Excavation 1Save > New

2. Stage 4: Exca 2Activate Tunnel Wall 1Deactivate Tunnel Excavation 2Save > New

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Create Construction Stages

1. Stage 5: Exca 3Activate Tunnel Wall 2Deactivate Tunnel Excavation 3Save > New

2. Stage 6: Exca 4Activate Tunnel Wall 3Deactivate Tunnel Excavation 4Save > New

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Create Construction Stages

1. Stage 7: Exca 5Activate Tunnel Wall 4Deactivate Tunnel Excavation 5Save > New

2. Stage 8: Exca 6Activate Tunnel Wall 5&6Deactivate Tunnel Excavation 6Save > Close

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Create Construction Stages

1. Make Copy of Stage Set.

Change name to No Piles> Define CS

2. Go to stage 2, modify case by removing piles

Save > Close

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Create Analysis Cases

1. Make Analysis Casefor Construction Set with Piles

2. Make Analysis Casefor Construction Set No Piles

3. Click Analysis ControlSet up as shown for both.

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Run Analysis

1. Perform Analysis on both cases.

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Inspect Results

1. Check Total Translation for case with No Piles

2. Compare to Case with Piles

3. Use Clipping Plane to see tunnel better

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Inspect Results

Deactivate all mesh sets except building and raft1. Check Total Translation for case

with No Piles

2. Compare to Case with Piles

3. Use Probe to get table values of building nodes

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Inspect Results

1. Check Axial Forces for Case with Piles

2. Check Moments Y

3. Check Shear Forces Z

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Export Results

1. Results > Advanced > ExtractSelect Piles Analysis CaseSelect Displacements > Total TranslationSelect top corner node of building #615Click TABLERepeat for No Piles Analysis Case

2. Select columns and Export to Excel to Graph results

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END