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Structural Concrete - Hassoun

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14.11 Basement Walls 515<br />

No. 4 @ 12″<br />

No. 4 @ 12″<br />

No. 4 @ 12″<br />

No. 4 @ 10″<br />

No. 5 @ 10″<br />

Uniform<br />

load<br />

Triangular<br />

load<br />

B B B<br />

R B = 1.30 K<br />

W<br />

M A = wL/8<br />

W<br />

H a =<br />

1.49 K<br />

10/3′<br />

A A A<br />

W = Total load<br />

M A = wL/7.5<br />

0.30 ksf<br />

H w =<br />

1.56 K<br />

0.31 ksf<br />

H s =<br />

1.54 K<br />

5′<br />

0.054 ksf<br />

7.6′ C<br />

– 7.40 K ∙ ft<br />

+<br />

4.3′<br />

9.75′ 10′<br />

+ 3.17 K ∙ ft<br />

R A = 4.44 K<br />

Figure 14.16<br />

Example 14.3: Basement wall.<br />

H s of the surcharge acts at h∕2 = 5 ft from the base<br />

P s = C a wh s = 0.271 × 0.110 × 1.82 = 0.054 ksf<br />

H s = C a wh s × h = 0.054 × 10 = 0.54 K∕ft of wall<br />

In the preceding calculations, it is assumed that the backfill is dry, but it is necessary to investigate<br />

the presence of water pressure behind the wall. The maximum water pressure occurs when<br />

the whole height of the basement wall is subjected to water pressure, and<br />

P w = wh = 62.5 × 10 = 625 psf<br />

H w = wh2<br />

2<br />

=<br />

0.625 × 102<br />

2<br />

= 3.125 K∕ft of wall

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