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Design of Steel Structures Part 2 doc

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DD ENV 1993-1-3:2001
© BSI 22 August 2001
xi
i) 5.8(5)P
When using Table 5.2, the value of f
bv
should be calculated using the formulae for webs without stiffening
at the support, irrespective of whether stiffeners are present or not.
j) 5.8(6)
The correct interpretation for k
r
is:
k) 5.9.2
For I-beams with restraint against web rotation, the method given in 5.3 of BS 5950-5:1998 may be used.
6.6 Chapter 6 Buckling resistance
a) Expression 6.4a
Expression 6.4a is incorrect and should be replaced by the following expression
= (f
yb
/B
cr
)
0,5
["
A
]
0,5
b) 6.2.3 Torsional buckling and torsional-flexural buckling
All sections should be checked for torsional, torsional-flexural and flexural buckling.
c) 6.2.3(1)P
An example of a point-symmetric open cross-section is a Z-section with similar flanges.


d) 6.2.3(7)P
For non-symmetrical cross-sections, the maximum stress should be determined by second-order analysis.
e) 6.3(1)P
Alternatively, M
cr
can be obtained from 6.6.2.2 of BS 5950-5:1998, its value being that of M
E
.
f) 6.4 Distortional buckling
For distortional buckling, reference should be made to AS/NZS 4600:1996 or a geometrical non-linear
analysis could be carried out using suitable initial imperfections.
g) 6.5 Bending and axial compression
All members subject to combined bending and axial compression should be designed in accordance with
the recommendations given in 6.4 of BS 5950-5:1998.
6.7 Chapter 7 Serviceability limit states
a) 7.3 Deflections
The designs for deflections should follow the provisions in clause 4, in particular, Table 4.1 and 4.2.3
of ENV 1993-1-1:1992.
b) 7.3(3)
There is no limit to the deflection of purlins, provided the provisions in 4.2.3 of ENV 1993-1-1:1992 are
complied with in respect of the supporting structure.
c) 7.4(2)
Serviceability limits for sheeting should be obtained from BS 5427-1 and BS 5950-6.
k
r
534
210,
t
-
I

s
s
d

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+,=
2

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