M

156.8 x 106

c,eff I

Curvature of the cracked section is given by 1 M 156.8 x 106

c,eff n

Having obtained the values for the two limiting conditions Eqn A.4.1 is used to assess the intermediate value.

Hence 1

For high bond bars, |31 = 1.0 For sustained loading, /32 = 0.5

<7s is the stress in the tension steel calculated on the basis of a cracked section Therefore

<xM (d - x) 25.64 x 156.8 x 106 (390 - 134.6) = 188.5 N/mm2

n ffg. is the stress in the tension steel calculated on the basis of a cracked section under the loading which will just cause cracking at the section considered.

Therefore a =

Therefore r = 1

Note:

— may be replaced by —'' in the above calculation ff M

1 = [(0.88 x 3.69) + (1-0.88) x 2.668] x 10~6 = 3.567 x 10"6 rad./mm

10.1.3.2.2 Shrinkage curvature

The shrinkage curvature is given by f = ecs«ef A.4.3.2

where e is the free shrinkage strain

For internal conditions and 2A lu = 165 mm 3.1.2.5i5

0 0

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