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A beam is singly reinforced with the reinforcement in two rows. The bottom row contains 9 No. 6 bars at a depth of 14 in. The top row contains 7 No. 5 bars at a depth of 8 in. Determine the effective (centroidal) depth, d, of the steel.

Fatigue failures of reinforced concrete structures are common.

A simply supported beam with dimensions of b = 14 in., h = 26 in., d = 23.5 in., and L = 18 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 1.0 kips/ft. The concrete is normal-weight concrete. The beam is reinforced with 3 No. 8 bars. The concrete strength is 6,400 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.      

During serviceability calculations, it is common to ignore the presence of compression reinforcement.

Concrete covers less than 2 in. may be required for durability, for fire resistance, or in members such as footings.

Compute the maximum bar spacing, s, to control for cracks in a one-way slab with 1.5 in. of clear cover and f​y​ = 62 ksi.

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. 6 Grade 60 bars. The concrete strength is 7,900 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the modulus of rupture of the concrete, fr.

Reinforced concrete structures normally do not crack when carrying service loads.

The fatigue strength of longitudinal bars is greater than that of stirrups.

What does the symbol M​cr ​represent in the transition from I​g​ to I​cr ​equation?