Other designdetailing checks

a) Minimum area of reinforcement

A6,min = 0.26 (fctm / fyk) M > 0.0013 btd where bt = width of tension zone fctm = 0.30 X fck 0667

b) Secondary (transverse reinforcement) Minimum 20% Aareq 20% Aareq = 0.2 x 502 = 100 mm2 / m

Consider As,min to apply as before.

Check edge

Assuming partial fixity exists at edges, 25% of As is required <9.3.1.2(2)>

to extend 0.2 x the length of the adjacent span. Asreq = 25% x 639 = 160 mm2 / m

Curtail 0.2 x 5975 = 1195 mm, say 1200 mm measured from face of support** <9.3.1.2(2)>

c) Maximum spacing of bars, < 3h < 400 mm OK <9.3.1.1.(3)>

d) Crack control

As slab < 200 mm, measures to control cracking are <7.3.3(1)> unnecessary.

However, as a check on end span: <7.3.3(2), 7.3.1.5> Loading is the main cause of cracking

.*. use Table 7.2N or Table 7.3N for wmax = 0.4 mm and cr= 241 MPa (see deflection check),

Max. bar size = 20 mm <Table 7.2N & interpolation or max. spacing = 250 mm <Table 7.3N & interpolation>

e) End supports: effects of partial fixity

Assuming partial fixity exists at end supports, 15% of As is <9.3.1.2(2)>

required to extend 0.2 x the length of the adjacent span. Asreq = 15% x 639 = 96 mm2 / m

But, Asmin as before = 216 mm2 / m <9.3.1.1, 9.2.1.1>

One option would be to use bob bars, but choose to use U-bars

Try H12 @ 450 (251 mm2 / m) U - bars at supports Curtail 0.2 x 5975 = say, 1200 mm measured from face of support++ <9.3.1.2(2)>

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