Civil Engineering Reference
In-Depth Information
Chapter 4
Continuous beams and slabs,
and beams in frames
4.1
Introduction
A continuous beam in a building may be interrupted by its supporting
internal columns; and these members are usually part of a framed structure.
The type of beam-to-column joints used influences the global analysis of
all the members in their vicinity. The terminology and definitions for
joints used in EN 1994-1-1 follow those given in EN 1993-1-8,
Design of
joints
[10], which are now summarised.
•
Connection
: location at which two members are interconnected, and
assembly of connection elements and - in the case of a major axis
joint - the load introduction into the column web panel.
•
Joint
: assembly of basic components that enables members to be
connected together in such a way that the relevant internal forces and
moments can be transferred between them.
Thus, the joint in Fig. 5.2(b), between a beam and an interior column,
consists of two connections. Each connection consists of a beam end-
plate, a column flange and six bolts, plus a share of the column web panel.
This panel is part of both connections.
The column is part of a frame in the plane of the diagram. It could also
be part of another frame, the beams of which would be attached to its web
(e.g., as in Fig. 5.2(c)). This 'joint' then has two more 'connections'; but
in practice this four-connection assembly is designed and detailed as two
joints, one in each frame, without interaction between the two designs.
The term 'joint' is sometimes used less precisely, both here and in the
Eurocodes, where the context is obvious.
Beam-to-column joints are classified both by stiffness and by strength.
The categories are:
•
for stiffness: rigid, semi-rigid, and nominally pinned;
•
for strength: full-strength, partial-strength, and nominally pinned.
122
