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Final Project 2010
E. Tarallo, G. Mastinu
POLITECNICO DI MILANO, Dipartimento di Meccanica
Summary
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Guidelines to the project:
 The project may be performed by group of a maximum 3
students;
 A complete report must be produced about the project;
 The report must include: a complete description of
geometries, properties, interactions and meshes; a study of
convergence; critical considerations about assembly
method (i.e., position and number of bolts);
 The complete work together with the exercise-book must
be delivered at least one week before taking the exam.
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The considered frame
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The considered frame
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The considered frame
* All the drawings have been put in the website as pdf formats
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Loads
6
A
Type
A(kN)
B(kN)
C(kN)
D(kN)
1
250
250
150
100
2
250
-250
150
100
3
250
250
-150
-100
B
C
D
*All the directions in this figure are POSITIVE
*The position of the forces A and B should be extracted from the drawings
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Different Analysis
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 Modeling:
1. Beam Elements (use constant section)
2. Shell Elements (use constant thickness)
3. Solid Elements (check welded or bolted joints)
 Analysis:
A. Static general (use constant loads and right boundary)
B. Frequency linear perturbation (find first 5 natural frequency)
C. Dynamic, implicit (use sinusoidal input of amplitude equal to
static load and variable frequency – look at phase problem)
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Appendix A – welded joints
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Main guidelines to verify a welding:
• Standard: UNI EN 1993: Eurocodice 3: Progettazione delle strutture
di acciaio Parte 1-8: Progettazione dei collegamenti
• Consider only fillet-weld
• According to the prismatic stress status:

 ||

 ||
normal stress perpendicular to throat
normal stress parallel to the axis of weld
shear stress perpendicular to the axis of weld
shear stress parallel to the axis of weld
•   is not considered when verifying the
design resistance of the weld
• Welds between parts with different material strength grades should
be designed using the properties of the material with the lower
strength grade.
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Appendix A – welded joints
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• The design resistance of the fillet weld will be sufficient if the
following are both satisfied:
 2  3 2   ||2  
fu
 w M 2
 
0.9  f u
M2
where:
fu is the nominal ultimate tensile strength of the weaker part joined;
 w is the appropriate correlation factor taken from table;
 M 2 is 1.25.
• For simplified criteria see
the standard
• For other criteria see std
CNR 10011
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Appendix B – bolted joints
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Main guidelines to verify a bolted joint:
• Standard: UNI EN 1993: Eurocodice 3: Progettazione delle strutture
di acciaio Parte 1-8: Progettazione dei collegamenti
• Bolt classes: fyb (yeld stress) fub (ultimate stress)
• Category of bolted connections
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Appendix B – bolted joints
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Legend:
 Fv,Ed= the design shear force per bolt for the ultimate limit state
 Fv,Rd = the design shear resistance per bolt
 Fb,Rd = the design bearing resistance per bolt
 Fv,Ed,ser = the design shear force per bolt for the serviceability limit
state
 Fs,Rd,ser = the design slip resistance per bolt at the serviceability limit
state
 Ft,Ed = the design tensile force per bolt for the ultimate limit state
 Ft,Rd = the design tension resistance per bolt
 Bp,Rd = the design punching shear resistance of the bolt head and
the nut
 A = the gross cross-section area of bolt
 As = the tensile stress area of the bolt or of the anchor bolt
 d = diameter of the bolt
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Appendix B – bolted joints
Positioning of the holes of bolts:
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Appendix B – bolted joints
Design resistance for individual bolt
subjected to shear and/or tension
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