Civil Engineering Reference
In-Depth Information
Check Cross-section
Assume a clear concrete cover of 38 mm (1.5 in.) and No. 4 bars (
d
b
=
13 mm) for web
reinforcement:
1
2
[(1854
10
3
mm
2
2
)
A
oh
=
−
89)
+
(1791
−
89)] (1270
−
89)
=
2047
×
(3
,
174 in
.
p
h
=
−
+
−
+
−
=
.
.
(1854
89)
(1791
89)
2(1270
89)
5829 mm (229
5in
)
9754
7224
9754
−
e
=
(753
−
127)
−
508
=
494 mm (19
.
47 in
.
)at0
.
3
L
from support
d
=
y
t
+
e
=
517
+
494
=
1011 mm (39
.
81 in
.
)at0
.
3
L
from support
d
=
0
.
8
h
=
0
.
8(1270)
=
1016 mm (40 in
.
)
governs
1
2
(267
t
=
+
235)
=
251 mm (9
.
875 in
.
)
b
w
=
2
t
=
2(251)
=
502 mm (19
.
75 in
.
)
10
3
mm
2
2
)
b
w
d
=
502(1016)
=
510
×
(790 in
.
The interaction equation for hollow box sections is
V
u
b
w
d
T
u
p
h
1
V
c
b
w
d
+
667
f
c
(MPa)
+
≤
φ
.
0
7
A
oh
.
10
3
5829
×
A
oh
p
h
=
2047
=
.
.
>
=
.
.
.
351 mm (13
8in
)
t
251 mm (9
875 in
)
=
t
251 mm governs
V
u
b
w
d
10
3
10
6
T
u
1038
×
657
.
4
×
+
=
+
10
3
)(251)
=
2
.
79 MPa (404 psi)
1
.
7
A
oh
t
510
×
10
3
1
.
7(2047
×
0
b
w
d
05
f
c
(MPa)
82(MPa)
V
u
d
M
u
V
c
=
.
+
4
.
where
V
u
d
M
u
≤
1
10
3
(1016)
9227
V
u
d
M
u
=
1038
×
=
0
.
1143
<
1OK
×
10
6
05
√
48
10
3
)
V
c
=
[0
.
.
2
+
4
.
82(0
.
1143)](510
×
=
458 kN (102
.
9kips)
166
f
c
(MPa)
b
w
d
166
√
48
10
3
)
V
c
,
min
=
0
.
=
0
.
.
2(510
×
=
588 kN (132
.
2kips)
>
458 kN
V
c
,
min
=
588 kN governs
V
c
b
w
d
+
(MPa)
90
588
2
667
√
48
667
f
c
10
3
×
φ
0
.
=
0
.
10
3
+
0
.
.
=
0
.
90(5
.
784)
510
×
=
5
.
20 MPa (753 psi)
>
2
.
79 MPa (404 psi) OK
