Design grid line
Effective depth, d d = 300 - 30 - 20 - 20 / 2 = 240 mm Flexure: column strip, sagging: MEd = 75.5 kNm / m
By inspection, z = 228 mm <Concise EC2 Table 15.5>
As = MEd / fydz = 75.5 x 106 / (228 x 500 / 1.15) = 761 mm2 / m
Deflection: column strip: By inspection, OK. Flexure: middle strip, sagging: MEd = 37.1 kNm / m By inspection, z = 228 mm As = MEd / fydz = 37.1 x 106 / (228 x 500 / 1.15) = 374 mm2 / m
By inspection, deflection OK. Try H10 @ 200 B2 (393 mm2 / m)
Flexure: column strip, hogging: MEd = 113.3 kNm / m
K = MEd / bd2fck = 113.3 x 106 / (1000 x 2402 x 30) = 0.065 <Concise EC2 Table 15.5>
As = MEd / fydz = 113.3 x 106 / (225 x 500 / 1.15) = 1158 mm2 / m
Flexure: middle strip, hogging: MEd = 18.5 kNm / m By inspection, z = 228 mm
As = MEd / fydz = 18.5 x 106 / (228 x 500 / 1.15) = 187 mm2 / m <Concise EC2 Table 15.5>
As before minimum area of reinforcement governs
As,min = 0.26 x 0.30 x 300666 x 1000 x 240 / 500 = 361 mm2 / m <9.3.1.1, 9.2.1.1>
Requirements:
Regarding the requirement to place 50% of At within a width equal to 0.125 of <9.4.1(2)>
ssss The hogging moment could have been considered at face of support to reduce the amount of reinforcement required.
the panel width on either side of the column. Area required = (3.0 x 1158 + 6.1 x 187) / 2 mm2 = 2307 mm2
Within = 2 x 0.125 x 6.0 m = 1500 mm centred on the column centreline.
i.e. require 2307 / 1.5 = 1538 mm2 / m for 750 mm either side of the column centreline.
Use H20 @ 200T2 (1570 mm2 / m) 750 mm either side of centre of support (p = 0.60%)
In column strip, outside middle 1500 mm, requirement is for 3.0 x 1158-15 x 1570 = 1119 mm2 in 1500 mm, i.e. 764 mm2 / m
Use H16 @ 250 T2 (804 mm2 / m) in remainder of column strip
In middle strip

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