IDEA Connection New CBFEM design of steel · PDF fileIDEA Connection New CBFEM design of steel joints Lubos Sabatka Erlenbach, September 02, 2014 ... • Software: IDEA StatiCa Concrete

IDEA ConnectionNew CBFEM design of steel joints

Lubos SabatkaErlenbach, September 02, 2014

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Range of steel joints

IDEA Connection release

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Range of steel joints

IDEA Connection release

IDEA Connection release

TA CR project - preparations

Is it possible to analyze steel joints in more precise and general way? Years of searching for the solution, discussions, trials and errors

Research and development team:• FCE CTU Prague – prof. František Wald, Lukáš Godrich, Marta

Kurejková• FCE BUT Brno – prof. Miroslav Bajer, Jan Barnat, Martin Vild, Josef

Holomek• IDEA RS – Lubomír Šabatka, Jaromír Kabeláč, Martin Pospíšil,

Drahoš Kolaja, Lukáš Hron, Lukáš Heryan

Technical background:• Long-term experience with development of CM• Practical experience with design of steel structures• Approved professional experience with FEM and sw development

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IDEA Connection release

TA CR project - goals

The goal is to develop method and tools for the analysis and check of steel joints of general shape and load

Method has to be:

general so that it is useable for most of joints, anchors, and details used in building practice

simple and fast so that it provides results in time comparable with currently existing methods and tools

comprehensible so that structural engineer gets clear information about joint behavior, stress, strain and reserves of individual components and about overall safety and reliability

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IDEA Connection release

Component Based Finite Element Model

CBFEM

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Synergy of standard Component method and Finite Element Analysis

Unique patented solution of model composition

IDEA Connection release

1.Reinforcing too late …2. Why so many bolts?

3. There are thousands of them…

4. Sometimes it can’t fit in

5. Does everybody really know?

6. Plates are estimated

7. Everything in 3D

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Chord of truss girder – change of profile depth

FEA analysis with elastic material – maximal stress 550 MPa. Yield strength is 235 MPa …

How useful is such an analysis?

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IDEA Connection release

Steel – plastic nonlinear analysis

Material models of steel for research and design oriented methodsCheck of plates is done for limit equivalent plastic strain – 5% in EC3

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Designed by IDEA Connection

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Equivalent plastic strain

12%

4,5%

0,5%

IDEA Connection release

IDEA Connection release

IDEA Connection release

1. Reinforcing too late …

2.Why so many bolts?3. There are thousands of them…

4. Sometimes it can’t fit in

5. Does everybody really know?

6. Plates are estimated

7. Everything in 3D

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IDEA Connection release

Bolt in tension

Huge bracing diagonal, visible bolted connection, special (expensive) bolts

Number of bolts needs to be optimized

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Designed by IDEA Connection

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Editor of plate shapes.Editor of bolt positions.

Bolted connection of any topology can be designed.

IDEA Connection release

IDEA Connection release

Bolt in tension

Bolted connection = steel plates in contact + bolts

Bolts are modeled as nonlinear springs

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IDEA Connection release

Verification

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Welded portal frame moment connection• CBFEM model was verified by the CM • Sensitivity study

• column HEB 260 + variable size of beam IPE css• variable size of column HEA css + beam IPE 330

• ULS resistance was calculated representing force couple My and Vz

• Resistance was governed by two components• column panel in shear • beam flange in compression

IDEA Connection release

Verification - welded portal frame moment connection

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0

50

100

150

200

250

120 160 200 240 280 320 360 400 440 480 520

Resistan

ce M

y/Vz [k

Nm / kN]

Beam cross‐section IPE

CM model

CBFEM model

IDEA Connection release

IDEA Connection release

1. Reinforcing too late …

2. Why so many bolts?

3.There are thousands of them… 4. Sometimes it can’t fit in

5. Does everybody really know?

6. Plates are estimated

7. Everything in 3D

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IDEA Connection release

A very common joint …

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Designed by IDEA Connection

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Original Haunch without flange Simpler solution

IDEA Connection release

IDEA Connection release

Manufacturing operations• IDEA Connection does not work with connection

types, but with operation types. They can be combined in one joint - interaction.

• Operation types: Cut, base plate, end plate, plate to plate, fin plate, gusset plate, stub, splice, stiffener, widener (haunch), rib, opening, …

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IDEA Connection release

IDEA Connection release

1. Reinforcing too late …

2. Why so many bolts?

3. There are thousands of them…

4.Sometimes it can’t fit in5. Does everybody really know?

6. Plates are estimated

7. Everything in 3D

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IDEA Connection release

Concrete, anchoring

• Concrete block is modeled as Winkler-Pasternak subsoil

• There is a contact element between concrete and steel base plate

• Contact stress is evaluated• Check is done on average stress

from effective area

• Anchor bolts are like nonlinear springs

• Shear force is checked against friction, shear iron or bolts

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Designed by IDEA Connection

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Both bending moments – My and Mz.Irregular shape of base plate. Arbitrary positions of anchors.Opening in column web.

IDEA Connection release

IDEA Connection release

Validation, testing

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IDEA Connection release

Validation, testing

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IDEA Connection release

Validation, testing

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IDEA Connection release

IDEA Connection release

1. Reinforcing too late …

2. Why so many bolts?

3. There are thousands of them…

4. Sometimes it can’t fit in

5.Does everybody really know?6. Plates are estimated

7. Everything in 3D

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IDEA Connection release

Optimization of connection parts

100% 142,3% 143,4% 149,1%

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159,0%

Steel joint - Component Model

Joint is divided into componentsBehavior of each component is definedModel of all components is composed, internal forces in

each component are calculatedEach component is checked acc. to specific formulas

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Steel joint - Component Based Finite Element Model

Joint is divided into componentsAll steel plates are modeled by FE Bolts and welds are modelled as nonlinear springsFE Model is used for analysing of internal forces in each

componentEach component is checked acc. to specific formulas like in

Component Method

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CBFEM – Component Based Finite Element Model

The mesh of different components is not influenced.

IDEA Connection release

IDEA Connection release

IDEA Connection release

1. Reinforcing too late …

2. Why so many bolts?

3. There are thousands of them …

4. Sometimes it can’t fit in

5. Does everybody really know?

6.Plates are estimated7. Everything in 3D

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IDEA Connection release

Bolt in shear

Bolts are modelled as nonlinear springs also for shear effects.Bolts are in contact with steel plate boreholes only in zone of pressure.Distribution of shear force from bolt to borehole surface is realized byspecial contact elements and interpolation constrains.Solution is protected by patent.

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Designed by IDEA Connection

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Gusset or splice plates are usually only estimated. Thickness is not optimized.

IDEA Connection analyses both simple and complex plates properly.

IDEA Connection release

IDEA Connection release

Report, overal results

Levels of content:• 1 line• 1 page A4• Detailed

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IDEA Connection release

IDEA Connection release

1. Reinforcing too late …

2. Why so many bolts?

3. There are thousands of them…

4. Sometimes it can’t fit in

5. Does everybody really know?

6. Plates are estimated

7.Everything in 3D

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IDEA Connection release

Designed by IDEA Connection

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CBFEM method is not limited by the shape and topology of steel joint. More different connection types can be implemented in one joint.Each member can be loaded by all 6 internal forces.

20 sec

IDEA Connection release

Joint templates

New CBFEM method is able to analyze steel joint of any complex shapeWhat about simple common connections?

Any joint designed in IDEA Connection can be saved „as template“

Any template can be reused for joint of similar topology.• Different angles of members• Different cross-section dimensions• Different cross-sections type

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Joint templates

IDEA Connection release

IDEA Connection – development roadmap

Discussion started 10 years ago

The first version developed in last 12 monthsNew CBFEM method was introduced

Next development:

• Various manufacturing operations• Tuning of component behavior• Buckling check of steel joint• Stiffness analysis of connection of each member in the

joint• …

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Lubomír Šabatka, M.Sc., Ph.D.

• Leading development teams since 1986• The first Windows based software for structural analysis

in Europe back in the 90’s • Development director in Nemetschek SCIA• Programs: EPW (Nexis), SCIA Engineer

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• Founded 07/2009 • Development and distribution of

FEA programs• Partners: Midas IT, InterCAD• Software: IDEA StatiCa Concrete/

Steel / Prestressing

IDEA RS

IDEA Connection release

IDEA Connection – new product on the market

IDEA Connectionis released

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