A simply supported beam with dimensions of b = 14 in., h = 30 in., d = 27.5 in., and L = 21 ft supports a uniform service (unfactored) dead load of 2.1375 kips/ft including its own self weight plus a uniform service (unfactored) live load of 1.4 kips/ft. The beam is reinforced with three No. 5 Grade 60 bars. The concrete strength is 4,000 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 = 6,462.8 in.4.

A rectangular beam has a cross section of b = 18 in., h = 22 in., and d = 19.5 in. It is reinforced with two No. 7 Grade 60 bars. The concrete strength is 8,800 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 3.411 in.

A rectangular beam has a cross section of b = 16 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 cracked moment of inertia, Icr. The neutral axis location of the cracked beam (measured from the top of the beam) is 4.4232 in.

States at which the structure becomes unfit for its intended function are called liability states.

A rectangular beam has a cross section of b = 16 in., h = 24 in., and d = 21.5 in. It is reinforced with two No. 7 Grade 60 bars. The concrete strength is 4,600 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the transformed cross-sectional area of the bars, Ast.

Serviceability limit states deal with collapse of the structure, whereas strength limit states deal with disruption of the use of the structure but not collapse.

The straight line theory is an elastic calculation that gives a good estimate of the concrete and steel stresses at service loads. It is used to calculate the stiffness, EI, at service loads, for deflection calculations, and steel stresses, for use in crack-width or fatigue calculations.

The largest concrete stress in a reinforced-concrete beam occurs _______.

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

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. 5 Grade 60 bars. The concrete strength is 2,800 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 5.2594 in.