Torsion - Design of Reinforced Concrete - page 497

15.11 Determine the required spacing of #4 stirrups at a distance d from the face of the support for the beam shown if
the load is acting 3 in. off center of the beam. Assume that the torsion equals the uniform load times the 3 in., 3000
psi, and f y 60,000 psi. Use #4 stirrups. Assume that the torsion value varies from a maximum at the support to 0 at the
beam L , as does the shear. Assume 1.5 in. clear cover. ( Ans. 8.75 in.)

c f

15.12 Is the beam shown satisfactory to resist a T u of
15 ft-k and a V u of 60 k if 4000 psi and f y 60,000
psi? The bars shown are used in addition to those pro-
vided for bending moment.

15.13 Using the accompanying software, determine the
required spacing for #4 closed stirrups at a distance d
from the support for Problem 15.7. ( Ans. 7.75 in)

c

f

15.14 Repeat Problem 15.11 using #3 closed stirrups and
SABLE32 software.

Problems in SI Units

15.15 Determine the required spacing of #13 stirrups at a distance d from the face of the support for the beam
shown in the accompanying figure, assuming that the torsion decreases uniformly from the beam end to the beam L .
The member is subjected to a 34-kN m service dead load torsion and a 40 kN m service line load torsion at the
face of the support, f y 420 MPa and c f 24 MPa, clear cover 40 mm. ( Ans. 175 mm)