Post on 26-Mar-2018
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
IDEA Connection release 42
• 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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