F. K. Kong MA, MSc, PhD, CEng, FICE, FIStructE, R. H. Evans CBE, DSc, D ès Sc, DTech, PhD, CEng, FICE, FIMechE, FIStructE (auth.)-Reinforced and Prestressed Concrete-Springer US (1987)

Calculation of crack widths (BS 81 10) 189
0
en
..
<.0
"'tJ
~t ~
li
o . __ __,T_
_ Cm•40
(a)
Cm• 40 201--
~~
Ocr Cnf40
{b)
250 below N.A.
0
10
N
I
~
(d)
Fig. 5.6-1
fm = 0.001657 as in (a); x = 303.6 mm as in (a)
From eqn (5.6-1),
k "d h - (3)(64.85)(0.001657) - 0 29
crac WI t - [ ] - . mm
1 + 2 64.85 - 40
750- 303.6
(c) Tension face: midway between two bars. From Fig. 5.6-1(c), it is easy
to show that
acr = ~(82.5 2 + 60 2 ) - 20 = 82 mm
fm = 0.001657 as in (a)
x = 303.6 mm as in (a)
From eqn (5.6-1),