Nonlinear Static and Dynamic Analysis of Steel Structures with ...

Chapter 1 Design of steel structures with Eurocode 3
1.3.5 Loads, limit state criteria and partial factors
Loads
(1) The loads applied to the structures should include relevant load factors and load
combination factors. For simplicity a single load multiplier a may be used.
Limit state criteria
(1) The ultimate limit state criteria should be used as follows:
1. for structures susceptible to buckling: attainment of the maximum load.
2. for regions subjected to tensile stresses: attainment of a limiting value of the principal
membrane strain.
NOTE 1: The National Annex may specify the limiting of principal strain. A value of 5%
is recommended.
NOTE 2: Other criteria may be used, e.g. attainment of the yielding criterion or limitation
of the yielding zone.
Partial factors
(1) The load magnification factor au to the ultimate limit state should be sufficient to
achieve the required reliability.
(2) The magnification factor au should consist of two factors as follows:
1. a1 to cover the model uncertainty of the FE-modeling used. It should be obtained from
evaluations of test calibrations;
2. a2 to cover the scatter of the loading and resistance models. It may be taken as γΜ1 if
instability governs and γΜ2 if fracture governs.
(3) It should be verified that: au > a1 a2
NOTE: The National Annex may give information on γΜ1 and γΜ2. The use of γΜ1 and γΜ2
as specified in the relevant parts of EN 1993 is recommended.
1.4 Design of joints
1.4.1 Introduction
Joint is defined as the zone where two or more members are interconnected. For design
purposes it is the assembly of all the basic components required to represent the behaviour
during the transfer of the relevant internal forces and moments between the connected
members. A beam-to-column joint consists of a web panel and either one connection
(single sided joint configuration) or two connections (double sided joint configuration), see
Figure 1.4.
Connection is defined as the location at which two or more elements meet. For design
purposes it is the assembly of the basic components required to represent the behaviour
during the transfer of the relevant internal forces and moments at the connection.
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