Civil Engineering Reference
In-Depth Information
strength in the presence of external hydrostatic pressure, in stress units, such
that:
F
y
h
3B
i
p
09B
2
B
2
η
F
th
=
1
+
0
:
−
−
0
:
(3.62)
F
b,h
is the representative bending strength in the presence of external hydro-
static pressure, in stress units, and
=
γ
R,h
f
h
F
h
B
B
≤
1
:
0
4
F
h
F
y
η =
5
−
Axial Compression, Bending and Hydrostatic Pressure
Tubular members subjected to combined axial compression, bending and
hydrostatic pressure should be designed to satisfy the following requirements
at all cross-sections along their length.
q
f
by
+
γ
R,b
f
bz
γ
R,c
f
ac
F
yc
+
≤
1
:
0
(3.63)
F
bh
0, i.e. the member is in compression regardless of the capped-end
stresses,
Equation (3.64)
should also be satisfied.
If f
a
<
t
C
m,y
f
by
1
"
#
2
2
γ
R,c
f
c
F
c,h
+
γ
R,b
C
m,z
f
bz
1
+
≤
1
:
0
(3.64)
−
−
F
bh
f
c
/F
ey
f
c
/F
ez
where, additionally, F
c,h
is the representative axial compressive strength in the
presence of external hydrostatic pressure, in stress units.
s
"
#
2f
q
F
yc
+
f
q
F
yc
2
2
2
2
F
c,h
=
0
:
5F
yc
ð
1
:
0
−
0
:
278
λ
Þ −
ð
1
:
0
−
0
:
278
λ
Þ
+
1
:
12
λ
(3.65)
s
−
1
2f
q
F
yc
for
λ ≤
1
:
34
1
−
s
−
1
2f
q
F
yc
0
:
9
F
c,h
=
2
F
yc
for
λ >
1
:
34
1
−
(3.66)
λ
If the maximum combined compressive stress f
x
= f
b
+ f
ac
(if f
ac
≤
0) or f
x
=
f
b
−
0) and the elastic local buckling strength F
xe
exceeds the limits
given below, then
Equation (3.68)
should also be satisfied.
f
ac
(if f
ac
<
Search WWH ::
Custom Search