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

A beam is singly reinforced with the reinforcement in two rows. The bottom row contains 9 No. 5 bars at a depth of 24 in. The top row contains 7 No. 5 bars at a depth of 18.5 in. Determine the effective (centroidal) depth, d, of the steel.

A rectangular beam has a cross section of b = 16 in., h = 24 in., and d = 21.5 in. It is reinforced with five No. 7 Grade 60 bars. The concrete strength is 6,100 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 = 18 in., h = 28 in., and d = 25.5 in. It is reinforced with three No. 7 Grade 60 bars. The concrete strength is 9,700 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 4.6421 in.

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 = 14 in., h = 26 in., and d = 23.5 in. It is reinforced with four No. 5 Grade 60 bars. The concrete strength is 7,300 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the assumed modulus of elasticity of the concrete, Ec.

With time, concrete frames expand due to creep, while brick exteriors shorten due to an increase in moisture content above their kiln-dried condition.

A rectangular beam has a cross section of b = 18 in., h = 24 in., and d = 21.5 in. It is reinforced with four No. 6 Grade 60 bars. The concrete strength is 7,000 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).

Reinforcement surrounded by concrete will _______ until an electrolytic cell can be established.

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