L

Eqn 5.5

= 1 for straight bars; or

= 0.7 for curved bars with 30 transverse cover

Therefore

Therefore width of support required in Figure 8.6(a), assuming 20 mm cover and 15 mm chamfer w (a) = (-§-) x 33.30 + 35 = 22.20 + 35 mm and width of support required in Figure 8.6(b), assuming as above iv (b) = (-§-) x 23.30 + 35 = 15.50 + 35 mm

The minimum support width is given by wmjn = (-§-) x 100 + 35 = 6.70 + 35 mm where, in Figure 8.6(a), A < 0.3/4

a v ' s.req s,prov and, in Figure 8.6(b), A < 0.43/4

As noted above, aa = 0.7 can only be used if the concrete cover perpendicular to the plane of curvature is at least 30. This is clearly difficult to achieve in beams without end diaphrams for bar sizes in excess of 12 mm.

The requirements for the various types of hooks, loops and bends are given in EC2 Figure 5.2. The minimum diameters of mandrels are given in NAD(1) Table 8. The required support widths are given in Table 8.1.

Table 8.1 Width of support (mm)
0 0

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