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A 116-mm-long beam supports a load of P = 39 N at midspan. The cross section is rectangular with width b = 30 mm and height h = 55 mm. Determine the magnitude of the horizontal shear stress at the centroid of the cross section.

Which symbol represents the bar-spacing factor?

Determine the lightweight modification factor, λ, for a rectangular beam with b = 18 in. and d = 22 in., three uncoated No. 7 Grade 60 tension-reinforcement bars placed in the bottom of the beam, and No. 4 Grade 40 stirrups located every 6 in. along the span. Assume 8,000-psi lightweight concrete and a clear cover of 1.75 in.

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.

According to ACI 318, combinations of spirals, circular ties, and hoops can be used as web reinforcement.

A rectangular beam with cross section b = 16 in., h = 24 in., and d = 21.5 in. supports a total factored uniform load of 1.20 kips/ft, including its own dead load. The beam is simply supported with a 22-ft span. It is reinforced with four No. 5 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 7,500 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 = 117.9 kip-ft, and the strength of the remaining two bars is φMn = 59.48 kip-ft. Determine the distance from the support to the theoretical cutoff point (i.e. disregard 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 = 8,000 psi, fyt = 60,000 psi, b = 14 in., d = 17 in., and that there are four No. 9 longitudinal tension bars and No. 5 stirrups at 8 in. o.c. The stirrup hooks are 135°.

A rectangular beam with cross section b = 14 in., h = 26 in., and d = 23.5 in. supports a total factored uniform load of 1.80 kips/ft, including its own dead load. The beam is simply supported with a 19-ft span. It is reinforced with four No. 5 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 6,900 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 = 128.6 kip-ft, and the strength of the remaining two bars is φMn = 64.93 kip-ft. Determine the distance from the support to the theoretical cutoff point (i.e. disregard ACI 318-14 Section 9.7.3.3).

In deformed reinforcing bars, adhesion and lateral friction are significant sources of bond strength.

Paso 2 (3 pts) (1 pt per sentence: 0.5 pts meaning, 0.5 pts form) Mario is now talking about different people related to him. Select the most logical possessive adjective to complete each sentence.