Aj

sf vRd3 = 2.5 x 0.3 x 100 = 75 kN/m > vSd OK Eqn 4.35

No shear reinforcement required

4.1.3.1.10 Topping reinforcement

No special guidance is given in EC2 regarding the design of the flange spanning between ribs. The Handbook to BS 8110(13) gives the following guidance.

3.6.1.5 Thickness of topping used to contribute to structural strength Although a nominal reinforcement of 0.12% is suggested in the topping (3.6.6.2), it is not insisted upon, and the topping is therefore expected to transfer load to the adjacent ribs without the assistance of reinforcement. The mode of transfer involves arching action and this is the reason for the insistence that the depth be at least one-tenth of the clear distance between the ribs.

Minimum flange depths are the same in EC2 and BS 8110 and the above is 2.5.2.1(5) therefore equally applicable. Provide minimum reinforcement transversely and where top bars in rib, which have been spread over width of flange, are curtailed.

Therefore, conservatively A. <150 mm2/m

Use T8 @ 200 mm crs. (251 mm2/m) or consider fabric

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