IDEA Connection New CBFEM design of steel joints Lubos Sabatka Erlenbach, September 02, 2014 ingware.ch Mit dem Besten rechnen
3 Range of steel joints
4 Range of steel joints
5 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
6 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
7 Component Based Finite Element Model CBFEM Synergy of standard Component method and Finite Element Analysis Unique patented solution of model composition
8 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
9 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?
10 Steel plastic nonlinear analysis Material models of steel for research and design oriented methods Check of plates is done for limit equivalent plastic strain 5% in EC3
11 Designed by IDEA Connection Equivalent plastic strain 12% 4,5% 0,5%
12 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
13 Bolt in tension Huge bracing diagonal, visible bolted connection, special (expensive) bolts Number of bolts needs to be optimized
14 Designed by IDEA Connection Editor of plate shapes. Editor of bolt positions. Bolted connection of any topology can be designed.
15 Bolt in tension Bolted connection = steel plates in contact + bolts Bolts are modeled as nonlinear springs
16 Verification 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
17 Verification - welded portal frame moment connection 250 Resistance My/Vz [knm / kn] 200 150 CM model 100 CBFEM model 50 0 120 160 200 240 280 320 360 400 440 480 520 Beam cross section IPE
18 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
19 A very common joint
20 Designed by IDEA Connection Original Haunch without flange Simpler solution
21 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,
22 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
23 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
24 Designed by IDEA Connection Both bending moments My and Mz. Irregular shape of base plate. Arbitrary positions of anchors. Opening in column web.
25 Validation, testing
26 Validation, testing
27 Validation, testing
28 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
29 Optimization of connection parts 100% 142,3% 143,4% 149,1% 159,0%
30 Steel joint - Component Model Joint is divided into components Behavior of each component is defined Model of all components is composed, internal forces in each component are calculated Each component is checked acc. to specific formulas
31 Steel joint - Component Based Finite Element Model Joint is divided into components All steel plates are modeled by FE Bolts and welds are modelled as nonlinear springs FE Model is used for analysing of internal forces in each component Each component is checked acc. to specific formulas like in Component Method
32 CBFEM Component Based Finite Element Model The mesh of different components is not influenced.
33 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
34 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 by special contact elements and interpolation constrains. Solution is protected by patent.
35 Designed by IDEA Connection Gusset or splice plates are usually only estimated. Thickness is not optimized. IDEA Connection analyses both simple and complex plates properly.
36 Report, overal results Levels of content: 1 line 1 page A4 Detailed
37 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
38 Designed by IDEA Connection 20 sec 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.
39 Joint templates New CBFEM method is able to analyze steel joint of any complex shape What 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
Joint templates IDEA Connection release 40
41 IDEA Connection development roadmap Discussion started 10 years ago The first version developed in last 12 months New 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
42 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 RS Founded 07/2009 Development and distribution of FEA programs Partners: Midas IT, InterCAD Software: IDEA StatiCa Concrete/ Steel / Prestressing
43 IDEA Connection new product on the market IDEA Connection is released