Hydraulic Structures: Fourth Edition

be read off. These are then corrected for the mutual interference of piles,
the floor thickness and the slope of the floor, if any.
It must be realized that this procedure assumes throughout a uniform
permeability coefficient (k) (see Section 2.3.4).

(a) Pressure distribution corrections

(i) CORRECTION FOR MUTUAL INTERFERENCE OF PILES (C%) (SEE FIG. 9.8)

C 19 D / b 1

 (dD)/b (9.7)

whereDthe depth of the pile line whose influence has to be determined
on the neighbouring pile of depth d,dthe depth of the pile on which the

WEIRS AND BARRAGES 373

0

20

30

40

50

60

70

0.2 0.4 0.6 0.8

Depressedflo

or

1.0

P/

Hs

(%)

C 1  100 E

D 1  100 D

E

D

D 1

Sheet pile at end

Hs

C 1

D 1

d

Hs

b d

D

E

Values of 1/
 d/b

b

Fig. 9.6 Khosla’s pressure chart with end pile