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 Verb list: escribir – comprar – salir – desayunar – beber – regresar Ay, mami, ¡qué día tan intenso ayer! Por la mañana, yo [q34] de casa tarde sin poder comer. Paula solo [q35] tostadas. Entonces, a las 2:30, Paula y yo tuvimos hambre y nosotras [q36] un sándwich de pollo por 12 dólares en la cafetería. Después, yo [q37] un café con una tarta de chocolate. A las 5:30, mis amigos Paula y Juan [q38] a casa para preparar la cena. Y tú, ¿[q39] tu composición de español en la biblioteca o en tu casa?

Determine the bar-spacing factor, cb, for a simply supported rectangular beam with b = 24 in. and No. 3 stirrups. This beam has three No. 7 bars as longitudinal reinforcement. The clear cover is 1.5 in.

Epoxy-coated or galvanized reinforcement is used to increase corrosion problems.

Concrete cover may be decreased to increase a member’s fire resistance.

A rectangular beam has a cross section of b = 18 in., h = 24 in., and d = 21.5 in. It is reinforced with five No. 5 Grade 60 bars. The concrete strength is 6,400 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. Determine the strength φMn for this beam.

The hardest way to test the bond strength of bars in a laboratory is by the pull-out test.

A smooth bar embedded in concrete develops bond by _______ between the concrete and the bar and by a small amount of _______.

A rectangular beam has a cross section of b = 18 in., h = 30 in., and d = 27.5 in. It is reinforced with five No. 5 Grade 60 bars. The concrete strength is 8,800 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the modulus of rupture of the concrete, fr.

A simply supported beam with dimensions of b = 14 in., h = 26 in., d = 23.5 in., and L = 24 ft supports a uniform service (unfactored) dead load of 1.679167 kips/ft including its own self weight plus a uniform service (unfactored) live load of 1.4 kips/ft. The concrete is normal-weight concrete. The beam is reinforced with 5 No. 5 bars. The concrete strength is 10,000 psi, and the yield strength of the reinforcement is 60,000 psi. Determine the maximum applied bending moment due to the combined service loads (dead plus live), Ma.      

Compression-development lengths are shorter than tension-development lengths, because some force is transferred to the concrete by the bearing at the end of the bar and there are no cracks in such an anchorage region.