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Steel Designers' Manual - 6th Edition (2003)
Simple connections 751
Table 26.9 Design checks for column splices – ends prepared for contact in bearing
Check Description Design rule
no.
1a Essential detailing
requirements – flange
cover plate on the outside
See Fig. 26.22(a)
1b Essential detailing
requirements – flange
cover plate on the inside
See Fig. 26.22(b)
2 The presence of tension
due to axial load and moment
See section on tension
3 Tension capacity of the
cover plate
The net tension capacity of the cover plate (pyAfp)
must be greater than the applied tensile force (Ft)
4 Shear capacity of bolt The reduced shear capacity of the bolt
group connecting flange
cover plate to column flange
group (reduction factor ¥ SPs) must be greater than
the applied tensile force (Ft)
5 Bearing capacity of flange The bearing capacity of the flange cover
cover plate connected
to column flange
plates (SPbs) must be greater than the applied
tensile force (Ft)
6 Structural integrity of The tension capacity of the splice (checks 3, 4 and
splice 5) must be greater than the tying force (Ftie)
obtained from clause 2.4.5.3(c) of BS 5950: Part 1
Note: The design check numbers may not match the check numbers given in Ref 1.
normally taken directly in the floor slab. It is rare for column splices in simple
construction to transmit wind shears.
The design checks given in Table 26.9 are based on the above assumptions. These
design checks and the essential detailing requirements given in Fig. 26.22 give
empirical rules which preserve the continuity of the finished structure, give a splice
with a minimum of robustness and ensure erection stiffness. These design recommendations
can be used for splices with internal or external flange cover plates.
26.2.6.2 Ends not prepared for contact in bearing
Typical details for this type of column splice are shown in Fig. 26.23. Both parts of
the figure show that the column above and below the splice is the same serial size.
In this case the splice is constructed using web and flange cover plates and, where
required, packs are used to make up the differences in the web and flange thicknesses.
Where columns of different serial size are to be connected multiple packs
are necessary to take up the dimensional variations.
For this type of splice all the forces and moments are carried by the cover plates
and no load is transferred through direct bearing. The axial load in the column is
normally shared between the flange and web cover plates in proportion to their