S A straight bar referred to in this context, really means a “straight bar”. It could be
a stock length bar (see Clause 2.1 ), or it could be a bar cut from a stock bar without any bending being done.
L, LL These bars include cases where a 90º hook (cog) is added at one or each end as
dimensions ‘A’ and ‘C’. If you are in any doubt as to the use and specification of hooks and cogs, please re-read Chapter 6.
CC This shape allows for a small offset (dimension D ≥ 2db ) so that column bars
can be lapped, dimension ‘A’ represents the lap-splice. The crank dimension ‘C’ should
be no less than 6d b, but for smaller bars 300 mm is used. (See Clause 12.2.10 ).
It can also be used for beam bars.
T, HT, DT These are “closed ties”; used principally with rectangular members.
SH, SC, RT These are “open ties”; give easy access for fixing beam cages (See Chapter 13 ).
J, JJ These shape s should b e used where a small crank is required at bar ends to avoid
interference with intersecting steel. The shapes used to be known as “ bent-up”
bars for shear stress design in beams and slabs. They are now obsolete. (Dimension
‘D’ approximated the depth of the member, and the angle was 45º).
V, VL, VV If known, the angle of bend can be given. The other dimensions are of ten obtainable from the concrete shape.
A, AL, AV The latter t wo are logical ex tensions of shape A, similar to shape V above.
U This should be specif ied in lieu of shape LL if the overall dimension ‘B’ is less than about 200 mm; LL cannot be bent to that size.
H, HH Both of these bars are defined as having 180º hooks at one end or each end respectively as dimensions ‘A’ and ‘C’. For bars other than these and some fitments, hooks can be added as shown later.
An “L” shape with a hook at one end is defined by “LH”, whilst one with two hooks is called “LD”.
In addition to this combination are the letters “I” (means the hook is bent “into” the next bend) and “O” (means it is bent “outward” from the next bend).
See Figure 9.2.
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