The fatigue strength of concrete is not sensitive to stress concentrations.

What happens once the crack pattern has stabilized and the member is loaded further?

A rectangular beam has a cross section of b = 18 in., h = 22 in., and d = 19.5 in. It is reinforced with four No. 6 Grade 60 bars. The concrete strength is 4,300 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the cracking moment, Mcr.

A rectangular beam has a cross section of b = 16 in., h = 26 in., and d = 23.5 in. It is reinforced with two No. 8 Grade 60 bars. The concrete strength is 5,500 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the transformed cross-sectional area of the bars, Ast.

A beam is singly reinforced with the reinforcement in two rows. The bottom row contains 7 No. 7 bars at a depth of 18 in. The top row contains 3 No. 8 bars at a depth of 14.5 in. Determine the effective (centroidal) depth, d, of the steel.

Determine the bar-spacing factor, cb, for a simply supported rectangular beam with b = 20 in. and No. 3 stirrups. This beam has three No. 7 bars as longitudinal reinforcement. The clear cover is 1.6 in.

A rectangular beam has a cross section of b = 16 in., h = 30 in., and d = 27.5 in. It is reinforced with five No. 6 Grade 60 bars. The concrete strength is 5,200 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the modulus of rupture of the concrete, fr.

A rectangular beam has a cross section of b = 16 in., h = 28 in., and d = 25.5 in. It is reinforced with two No. 5 Grade 60 bars. The concrete strength is 6,100 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the modulus of rupture of the concrete, fr.

Compute the maximum bar spacing, s, to control for cracks in a one-way slab with 2 in. of clear cover and f​y​ = 66 ksi.

A simply supported beam with dimensions of b = 14 in., h = 26 in., d = 23.5 in., and L = 22 ft supports a uniform service (unfactored) dead load of 1.479167 kips/ft including its own self weight plus a uniform service (unfactored) live load of 0.9 kips/ft. The beam is reinforced with two No. 6 Grade 60 bars. The concrete strength is 7,300 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 = 5,939.7 in.4.