Fatigue failures of reinforced concrete structures are rare.

A rectangular beam has a cross section of b = 14 in., h = 28 in., and d = 25.5 in. It is reinforced with five No. 6 Grade 60 bars. The concrete strength is 9,400 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 5.7126 in.

The textbook author recommends the use of 180° stirrups throughout, except in certain cases where 90° stirrups are needed to prevent overlap.

Almost universally, all of the longitudinal bars in a column are the same size.

Determine the required splice length for the longitudinal bars in the following tied column. Assume that all of the longitudinal bars are in compression and that you will use a contact lap splice. Do not incorporate a reduction in length due to ACI 318-14 Section 10.7.5.2.1.Column width, b = 20 in.Column thickness, h = 24 in.Clear cover to ties = 1.5 in.Number of longitudinal bars = 4Size of longitudinal bars = No. 7Size of ties = No. 3Concrete strength = 6,500 psiYield strength of longitudinal bars = 60,000 psiYield strength of ties = 40,000 psi

ACI 318-14 Section 25.7.2.1 specifies that ties shall have a center-to-center spacing of at least (4/3)dagg.

Columns with spirals generally exhibits less ductility than columns without spirals.

Determine the required splice length for the longitudinal bars in the following tied column. Assume that all of the longitudinal bars are in compression and that you will use a contact lap splice. Do not incorporate a reduction in length due to ACI 318-14 Section 10.7.5.2.1.Column width, b = 22 in.Column thickness, h = 16 in.Clear cover to ties = 1.5 in.Number of longitudinal bars = 10Size of longitudinal bars = No. 10Size of ties = No. 3Concrete strength = 9,000 psiYield strength of longitudinal bars = 60,000 psiYield strength of ties = 40,000 psi

Tied columns have lower ductility giving less warning before a failure.

Spiral column reinforcement restrains the _______ expansion, making a column more _______.