In-plane bending of beams - The Behaviour and Design of Steel Structures to EC3 - page 219

q D =60 kNm
q I =70 kNm

b f

t f

t w

4 @ 1 . 5 = 6 . 0m

h

(a) Examples 15, 17 and 18

Q D = 40 kN
Q I

b f = 229 mm A = 159 cm 2
h = 612.2 mm I z = 3932 cm 4
t f = 19.6 mm i z = 49.7 mm
t w = 11.9 mm W ,y = 3676 cm 3
r = 12.7 mm

= 120 kN

q D = 20 kN/m
q I = 10 kN/m

pl

3 . 0 m

(c) Example 16 (b) 610 229 UB 125 ×

Figure 5.44 Worked examples 15-18.

Classifying the section .

t f = 19.6 mm, f y = 265N/mm 2

EN10025-2

ε = ( 235 / 265 ) = 0.942 T5.2

c f /( t f ε) = ( 229 / 2 − 11.9 / 2 − 12.7 )/( 19.6 × 0.942 ) T5.2

= 5.19 < 9 and the flange is Class 1. T5.2

c w /( t w ε) = ( 612.2 − 2 × 19.6 − 2 × 12.7 )/( 11.9 × 0.942 ) T5.2

= 48.9 < 72 and the web is Class 1. T5.2

(Note the general use of the minimum f y obtained for the flange.)
Checking for moment .

q Ed = ( 1.35 × 60 ) + ( 1.5 × 70 ) = 186 kNm
M Ed = 186 × 6 2 / 8 = 837 kNm
M c , Rd = 3676 × 10 3 × 265 / 1.0 Nmm

6.2.5

= 974 kNm > 837 kNm = M Ed

which is satisfactory.