A rectangular beam has a cross section of b = 18 in., h = 26 in., and d = 23.5 in. It is reinforced with three No. 6 Grade 60 bars. The concrete strength is 6,700 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the assumed modulus of elasticity of the concrete, Ec.

A rectangular beam has a cross section of b = 18 in., h = 26 in., and d = 23.5 in. It is reinforced with two No. 7 Grade 60 bars. The concrete strength is 8,200 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the assumed modulus of elasticity of the concrete, Ec.

Reinforced concrete buildings are usually subject to vibration problems.

A simply supported beam with dimensions of b = 14 in., h = 24 in., d = 21.5 in., and L = 21 ft supports a uniform service (unfactored) dead load of 1.35 kips/ft including its own self weight plus a uniform service (unfactored) live load of 0.8 kips/ft. The beam is reinforced with four No. 8 Grade 60 bars. The concrete strength is 8,200 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Using the effective moment of inertia, determine the immediate mid-span deflection of the beam due to the combined service loads (dead plus live).The effective moment of inertia Ie = 8,139.1 in.4.

A rectangular beam has a cross section of b = 14 in., h = 26 in., and d = 23.5 in. It is reinforced with two No. 7 Grade 60 bars. The concrete strength is 10,000 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the gross moment of inertia, Ig, for the beam.

A rectangular beam has a cross section of b = 16 in., h = 22 in., and d = 19.5 in. It is reinforced with two No. 6 Grade 60 bars. The concrete strength is 2,500 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the transformed cross-sectional area of the bars, Ast.

A rectangular beam has a cross section of b = 16 in., h = 28 in., and d = 25.5 in. It is reinforced with three No. 8 Grade 60 bars. The concrete strength is 7,900 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the cracked moment of inertia, Icr. The neutral axis location of the cracked beam (measured from the top of the beam) is 5.7824 in.

A rectangular beam has a cross section of b = 14 in., h = 24 in., and d = 21.5 in. It is reinforced with four No. 7 Grade 60 bars. The concrete strength is 9,100 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the neutral axis location of the cracked beam (measured from the top of the beam).

A rectangular beam has a cross section of b = 16 in., h = 30 in., and d = 27.5 in. It is reinforced with three No. 8 Grade 60 bars. The concrete strength is 7,900 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the cracked moment of inertia, Icr. The neutral axis location of the cracked beam (measured from the top of the beam) is 6.0334 in.

At what ratio are the deflections of spans typically visible, where L is the span of the beam?