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Steel Designers' Manual - 6th Edition (2003)
30.1.2 Design of plates fixed on four edges
Steel plate floors 909
The plates must be secured by continuous bolting or welding, which will achieve the
fixed condition and prevent uplift which would otherwise occur at the plate corners.
The bolt or weld detail should be such as to develop the strength in bending of the
chosen plate thickness.
(1) Uniformly distributed loading
The design may be made using Pounder’s plate theory.
pt
w
kB k k
d m
2
=
È
˘
1+ ( - )+ ( - )
ÎÍ
˚˙
- kwB Ê
ˆ
= ¥ + ( -k)+
( -k)
m Et Ë
¯
11
35 1
79
141 1
1
47
1
32 210 1
200
517 1
2
y
2
2
2
4
2
2
3 g
where L = length of plate (mm) (L > B)
B = breadth of plate (mm)
t = thickness of plate (mm)
k =
py = yield stress of plate (N/mm2 )
w = uniformly distributed load on plate (ultimate) (N/mm2 )
E = Young’s modulus 205 ¥ 103 (N/mm2 4
Ê L ˆ
Á ˜
Ë 4 4
L + B ¯
)
1
= Poisson’s ratio (m = 3)
m
f
d = maximum deflection (mm), occurring at serviceability
gf = load factor
This formula is the basis of the third load table in the Appendix Floor plate
design tables.
(2) Centre point loads (concentrated over a small circle of radius r)
The design may be made using formulae developed by Roark. 1
2 067 . ppt
y
W =
Ê 1 ˆ 2B
1 + ln + b1
Ë m¯
pr
whichever is the lesser, where
or
2 pt y
b2
2 aWB
d =
3
g fEt
W = concentrated load (ultimate) (N)
d = maximum deflection (mm), occurring at serviceability
L = length of plate (mm) (L > B)
B = breadth of plate (mm)