In designing for shear, one must ensure that the shear strength equals or exceeds the flexural strength at all points in the beam.

A rectangular beam with cross section b = 16 in., h = 20 in., and d = 17.5 in. supports a total factored uniform load of 2.20 kips/ft, including its own dead load. The beam is simply supported with a 22-ft span. It is reinforced with four No. 8 Grade 60 bars, two of which are cutoff between midspan and the support and two of which extend 10 in. past the centers of the supports. The concrete strength is 5,100 psi (normal weight). The beam has Grade 60 No. 3 stirrups satisfying ACI 318-14 Sections 9.7.6.2.2 and 9.6.3.3. The strength of the four bars is φMn = 229.4 kip-ft, and the strength of the remaining two bars is φMn = 119.6 kip-ft. If the distance from the support to the theoretical cutoff point is 7.497 ft, determine the distance from the support to the actual cutoff point (i.e. use ACI 318-14 Section 9.7.3.3).

A continuous beam’s flexural reinforcement must extend at least _____ from the point where it is no longer needed to resist tension. Assume f’c = 3,500 psi, fyt = 60,000 psi, b = 10 in., d = 16 in., and that there are four No. 6 longitudinal tension bars and No. 5 stirrups at 10 in. o.c. The stirrup hooks are 135°.

Compute φVn for the cross section shown. Assume f’c = 4,000 psi, fyt = 60,000 psi, b = 15 in., d = 24 in., and that there are four No. 7 longitudinal tension bars and No. 5 stirrups at 6 in. o.c.

A continuous beam’s flexural reinforcement must extend at least _____ from the point where it is no longer needed to resist tension. Assume f’c = 4,000 psi, fyt = 40,000 psi, d = 23 in., w = 13.5 in., and t = 6 in. There are five No. 7 longitudinal tension bars and No. 5 stirrups at 6 in. o.c.

Teresa va a [q10] a caballo los fines de semana.

A combination of horizontal and vertical reinforcement is used to prevent cracks from being too narrow.

A rectangular beam with cross section b = 16 in., h = 20 in., and d = 17.5 in. supports a total factored uniform load of 2.20 kips/ft, including its own dead load. The beam is simply supported with a 22-ft span. It is reinforced with four No. 8 Grade 60 bars, two of which are cutoff between midspan and the support and two of which extend 10 in. past the centers of the supports. The concrete strength is 5,100 psi (normal weight). The beam has Grade 60 No. 3 stirrups satisfying ACI 318-14 Sections 9.7.6.2.2 and 9.6.3.3. The strength of the four bars is φMn = 229.4 kip-ft, and the strength of the remaining two bars is φMn = 119.6 kip-ft. If the distance from the support to the theoretical cutoff point is 7.497 ft, determine the distance from the support to the actual cutoff point (i.e. use ACI 318-14 Section 9.7.3.3).

In which type of splice is the force in one bar transferred to the concrete, which then transfers it to the adjacent bar?

Determine the size modification factor, ψs, for a rectangular beam with b = 18 in. and d = 20 in., five epoxy-coated No. 9 Grade 60 tension-reinforcement bars placed in the bottom of the beam, and No. 3 Grade 60 stirrups located every 6 in. along the span. Assume 4,000-psi lightweight concrete and a clear cover of 2 in.