For a beam with stirrup hooks, the free end of the bar must extend at least _____ from the hook. Assume b = 12 in., d = 23 in., and that there are four No. 6 longitudinal tension bars and No. 5 stirrups at 12 in. o.c. The stirrup hooks are 135°.

señores y señoras: a Josefina Fernández Dávila para el premio de mejor maestra del año. La señora Fernández es una maestra ejemplar y merece este premio y muchos más. Gracias por su . cordiales, Rosalía Pérez Guzmán

If φVc = 13 kip and Vu = 54 kip, are stirrups required?

A beam has dimensions of b = 14 in., h = 30 in., d’ = 2.5 in., and d = 27.5 in. It is reinforced with 2 No. 5 bars on the compression side and 4 No. 8 bars on the tension side. The concrete strength is 2,800 psi, and the yield strength of the reinforcement is 60,000 psi. For the results given below, determine the strength Mn for this beam.a = 4.828 in. (depth of concrete stress block)Cc = 159.4 kips (compressive force in concrete)Cs = 30.2 kips (compressive force in steel)T = 189.6 kips (tensile force in steel)

A beam has dimensions of b = 20 in., h = 12 in., and d = 9.5 in. and is reinforced with 4 No. 9 bars. The concrete strength is 3,800 psi, and the yield strength of the reinforcement is 60,000 psi. If the depth of the neutral axis is c = 4.371 in., does the reinforcement yield?

A simply-supported beam has a 1 kip/ft uniformly-distributed load over the entire 10-ft span. What is the magnitude of the maximum shear force in the beam?

Concrete cover helps to protect reinforcement against corrosion.

The largest moments in a continuous beam or a frame occur when some spans are loaded with live load and others are not. Influence lines are often used to determine which span should and should not be loaded.

A concrete floor system with a ratio of the longer to the shorter span length that is less than 2 is usually considered a two-way system.

A 121-mm-long beam supports a load of P = 30 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.