Civil Engineering Reference
In-Depth Information
12.24
Repeat Problem 12.22 as a plain concrete footing of uniform thickness if the live load is reduced to 6 k/ft.
In Problems
12.25
and
12.26
, design square plain concrete column footings of uniform thickness.
Reinforced
Distance from
concrete
bottom of footing
c
Problem
column size
D
L
f
q
a
to final grade
12
12
5
12.25
50 k
75 k
3 ksi
4 ksf
12.26
14
14
75 k
90 k
3.5 ksi
4 ksf
5
(
Answer to Problem 12.25:
6 ft 3 in.
6 ft 3 in. footing 28 in. deep)
Computer Problems
For Problems
12.27
to
12.30
, use the accompanying
software.
12.27
Repeat Problem 12.2. (
Ans.
14 ft 6 in. width, 27 in.
depth)
12.28
Repeat Problem 12.8.
12.29
Repeat Problem 12.10. (
Ans.
9 ft 3 in.
9 ft 3 in.,
26 in. depth)
12.30
Repeat Problem 12.16.
Problems with SI Units
In Problems
12.31
and
12.32
, design wall footings for the values given. The walls are to consist of reinforced con-
crete. Concrete weight
24 kN/m
3
, soil weight
16 kN/m
3
.
c
Problem
D
L
f
f
y
q
a
12.31
300 mm
150 kN/m
200 kN/m
21 MPa
420 MPa
170 kN/m
2
1.500 m
210 kN/m
2
12.32
400 mm
180 kN/m
250 kN/m
28 MPa
420 MPa
1.200 m
(
Answer to Problem 12.31:
370 mm footing, width
2.5 m, and #19 @ 225 mm main steel)
