Civil Engineering Reference
In-Depth Information
Maximum horizontal spacing of vertical stirrups:
w
3
(12)(10)
40
3
3
h
(3)(8)
24
18
18
k
Use #4 vertical stirrups 14
o.c. horizontally
6.
Design vertical flexural reinforcing:
M
u
(240)(14)
3360 ft- k @ base of wall
M
u
(12)(3360)(1000)
(0.9)(8)(96)
2
bd
2
607.6
0.0118 from Appendix Table A.12
A
s
bd
where
b
is wall thickness and
d
is again 0.80
w
(0.8)(12
10)
96
.
A
s
(0.0118)(8)(96)
9.06 in.
2
Use 10 #9 bars each end (assuming
V
u
could come from either direction)
7.
A sketch of the wall cross section is given in Figure 18.7.
18.7
ECONOMY IN WALL CONSTRUCTION
To achieve economical reinforced concrete walls, it is necessary to consider such items as
wall thicknesses, openings, footing elevations, and so on.
The thicknesses of walls should be sufficient to permit the proper placement and vi-
bration of the concrete. All of the walls in a building should have the same thickness if
practical. Such a practice will permit the reuse of forms, ties, and other items. Further-
more, it will reduce the possibilities of field mistakes.
Figure 18.7
