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)

From Table 6.4-2, use
Size 12 links at 300 mm
Shear resistance in design calculations (BS 8110) 217
Step 5 V> (ve + 0.4)
Figure 6.4-2(a) shows that shear reinforcement exceeding minimum
links is required for the regions within 2.29 m of B and within 0.93 m
of A.
Within 2.29 m of B
v = 2.09 N/mm 2 (see Step 1)
Ve = 0.7 N/mm 2 (see Step 4)
From eqn (6.4-3),
ve) = 350(2.09 - 0.70) = 224 mm
A sv = bv(v -
Sv 0.87/yv (0.87) (250) .
From Table 6.4-2, use
Size 12 links at 100 mm
Within 0.93 m of A (see Comments at the end):
v = (393.6) (10 3 )/(350) (800) = 1.41 N/mm 2
Ve = 0.61 N/mm 2 (see Step 4)
A sv = bv(v -
Sv 0.87/yv (0.87) (250) .
From Table 6.4-2, use
Size 12 links at 150 mm
ve) = 350(1.41 - 0.61) = 1 29 mm
The shear reinforcement provided is summarized in Fig. 6.4-2(b),
where the detailing notat ion is as explained in the question.
Comments on Step 1
The support moments are here taken as the redistributed moments, though
the designer may, if he so wishes, base both the ftexural and shear design
on the elastic moments.
Comments on Step 2
Here 0.8/ eu exceeds 5 N/mm 2 • Hence the effective ceiling is 5 N/mm 2 •
Comments on Step 3
Shear failures can be very dangerous, in that there may be no waroing
before disastrous collapse. Hence it is desirable to provide minimum links
even when the calculations show that the shear stress v is well below 0.5v c•
Comments on Step 4
When both top and bottom bars are present, as in Fig. 6.4-1, the area As
should properly be interpreted from the bending moment envelope. Thus,
the redistributed moment envelope in Fig. 4.9-7 shows that:
(a)
Within 1575 mm of the support B, the bending moment is always a