M

bd2f ck

300 x 440 x 32

Therefore compression reinforcement is required

s yk bdf ck

= w|im + w' = 0.1084 + 0.0750 = 0.1834 (Section 13)

Since d'lx = d'/0.208d = 0.546 > (1 - 1^/805) = 0.429

Use 4T25 (1960 mm2) top Use 2T25 (982 mm2) bottom

2.4.4.2 Near middle of 8 m span

From bending moment envelope M = 325 kNm

Effective flange width = 300 + 0.2 x 0.85 x 8000 = 1660 mm

325 x 106

1660 x 4502 x 32

Neutral axis is in flange since x = 31 < 175 mm

Use 4T25 (1960 mm2

From bending moment envelope

5 = 0.7 and yx|im = 0.0864 (Section 13, Table 13.2) 126 x 106

300 x 4402 x 32

'lim

Therefore no compression reinforcement is required.

Using 2T25 bent-up bars, minimum diameter of mandrel

2.4.4.4 Right-hand end of 6 m span

From bending moment envelope M = 76 kNm

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