BS4466 Bends and Shapes_

BS 4466 - Measurement of bending dimensions - 1989

In April 2000 a new British Standard the 'Specification for scheduling, dimensioning, bending and cutting of steel reinforcement for concrete' was

introduced; BS 8666 displacing BS 4466, the previous standard described here for reference purposes.

Use the links below for quick navigation around this page.

BS 4466 - Measurement of bending dimensions - 1989

Preferred Shapes

Non-Preferred Shapes

BS 4466 Notes

Bar Mass Data Table

Minimum former radii, bend and hook allowances

BS 4466 - Preferred Shapes

Method of measurement of

bending dimensions

Total length of bar (L) measured

along centre lineShape

Code

20

A

Shape

Code

32

A+h

Shape

Code

33

A+2h

Shape

Code

34

A+n

Where the overall dimension of the

bob is critical, use shape code 37.

Shape

Code

35

A+2n

Where the overall dimension of either

bob is critical, do not use this shape

code.

Shape

Code

37

A+(B)-½r-d

This formula is approximate. Where r

is greater than the minimum value in

table 3 BS 4466 1989, use shape code

51.

Shape

Code

38

A+B+(C)-r-2d


bending dimensions



Code

41

If angles with the horizontal are 45° or

less:

A+B+(C)

see note 4.

Shape

Code

43

If angles with the horizontal are 45° or

less:

A+2B+C+(E)

see note 4.

Shape

Code

51

A+(B)-½R-d

This formula is approximate, if R is

minimum, use shape 37. If R is greater

than 200mm, see note 2 to clause 10

BS 4466 1989.

Shape

Code

61

2(A+B)+12d

Neither A nor B are to be less than

12d or 150mm, whichever is the

greater, for grade 460 in sizes not

exceeding 20 mm nor less than 14d

for sizes of 25mm and over.

Neither A nor B are to be less than 10d for grade 250 with a

minimum value of A and B of 100mm. See note 3.

Shape

Code

62

If angle with horizontal is 45° or less.

A+(C)

See note 4.

Shape

Code

82

2A+3B+18d

If B is greater than 400+2d, see note 2

to clause 10 BS 4466 1989.

See note 3Notes:

for the BS 4466 notes - click here

BS 4466 - Quick Navigation go back

BS4466 Bends and Shapes: K B Rebar Limited http://www.kbrebar.co.uk/bs-4466

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BS 4466 - Non-Preferred Shapes


bending dimensions



Code

39

A+0.57B+(C)-1.57d

If B is greater than 400+2d, see note 2

to clause 10 BS 4466 1989

Shape

Code

42


A+B+C+n

See note 4.

Shape

Code

45


A+B+(C)-½r-d

See note 4.

Shape

Code

49


A+B+(C)

See note 4.

Shape

Code

52

A+B+C+(D)-1½r-3d

Shape

Code

53

A+B+C+D+(E)-2r-4d

Shape

Code

54

A+B+(C)-r-2d

Shape

Code

55

A+B+C+D+(E)-2r-4d

Shape

Code

65

A

These bars will be supplied straight

when the radius is greater than that

given in table 5 of BS 4466 1989


bending dimensions



Code

77

2A+B+20d

See note 3

Shape

Code

78

2A+B+C+3d

See note 3

Shape

Code

79

2A+3B+10d

Neither A nor B shall be less than 12d

or 150mm, whichever is the greater,

for grade 460 in sizes not exceeding

20mm not less than 14d for sizes of

25mm and over.

Neither A nor B are to be less than 10d for grade 250 with a

minimum value of A and B of 100mm. See note 3

Shape

Code

85

A+B+0.57C+(D)-½r-2.57d

If C is greater than 400+2d see note 2

to clause 10 BS 4466 1989

Shape

Code

87

where B is not greater than A/5.

C⁄B π (A-d) (L<12m)

Where A is the external diameter of

helix (in mm)

B is the pitch of helix (in mm)

C is the overall height of helix (in

mm).

Where B is greater than A/5 the

formula does not apply.

There shall be at least two full turns in the helix.

Note, unless A is small relative to d, this shape is fabricated in a

closed form and pulled to shape on site.

Shape

Code

99

All other shapes To be calculated

A dimensional sketch shall be drawn

out over schedule columns A to E.

Every dimension that is to allow for the permissable deviations

shall be indicated in parenthesis, otherwise the fabricator is free to

choose which dimension shall allow for the tolerance. If a shape

that is given in this table or in table 1 BS 4466 1989 is required but

a different dimension is to allow for the permissable deviations, the

shape code 99 & the free dimension shall be indicated in

parenthesis. The tolerances given in table 4 BS 4466 1989 also

apply.


Notes:

r indicates the minimum value in the table 3 BS 4466 19891.

The dimensions in parenthesis are the free dimensions2.

To avoid separate equations for each steel grade and bending radius,

simplified total length formulae are used for shape codes 61, 77, 78,

79 and 82. These formulae are necessarily approximate.

3.

The length formula is approximate and when bending angles exceed

45° the length should be calculated more accurately allowing for the

difference between the specified overall dimensions and the true

length measured along the central axis of the bar or wire. When the

bending angles approach 90°, it is preferable to specify shape code 99

with a fully dimensional sketch.

4.

BAR MASS per linear metre (kg/m) :-

50mm: 15.413kg/m 40mm: 9.864kg/m 32mm: 6.313kg/m 25mm: 3.854kg/m 20mm: 2.466kg/m

16mm: 1.579kg/m 12mm: 0.888kg/m 10mm: 0.616kg/m 8mm: 0.395kg/m 6mm: 0.222kg/m


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Minimum former radii, bend and hook allowances

Bar

Size

Grade 250 bars complying with the

requirements of BS 4449 (type and grade

R) and BS 6744 type S

d r † n h

6†‡ 12 100 100

8 16 100 100

10 20 100 100

12 24 100 110

16 32 100 150

20‡ 40 100 180

25‡ 50 130 230

32‡ 64 160 290

40‡ 80 200 360

50‡ 100 250 450

Bar

Size

Grade 460 bars complying with the

requirements of BS 4449 (type and grade

T) and BS 6744 type S

d r † n h

6†‡ 18 100 100

8 24 100 100

10 30 100 110

12 36 100 140

16 48 100 180

20‡ 60 110 220

25‡ 100 180 350

32‡ 128 230 450

40‡ 160 280 560

50‡ 200 350 700

Fabric

Size

Sheet Fabric complying with the

requirements of BS 4483

standard size 4.8m x 2.4m

d r † n h

5 15 100 100

6 18 100 100

7 21 100 100

8 24 100 100

9 27 120 135

10 30 120 135

12 36 130 145

**The use of hooks as end anchorages is not normally necessary with deformed bars.

† It should be borne in mind that special precautions such as reducing the speed of bending or increasing the radius of

bending may necessary in cold weather. For bending and rebending on site refer to BS 8110.

‡ Non-preferred size for grade 250 bars.

• Non-preferred size for grade 460 bars.

NOTE: These radii are the minimum radii of the formers for material complying with the relevant British standard. Certain

design situations may call for larger radii and for these the recommendations in BS 8100 should be followed.

Radius of bending:- maximum values requiring bending

Bar Size 6 8 10 12 16 20 25 32 40

Radius (m) 2.5 2.75 3.5 4.25 7.5 14 30 43 58

N.B. Bars to be formed to a radius exceeding the above

dimensions will be supplied straight.

see clause 8 BS 4466 1989

for definition of y.


K B Rebar Limited, Unit 5, Dobson Park Industrial Estate, Dobson Park Way, Ince, Wigan WN2 2DY.


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BS4466 Bends and Shapes_

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