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Compute the axial compressive strength Pn and moment capacity Mn of the following tied column when the largest strain in the concrete is 0.003 and the strain in the tension reinforcement is 0.003. Note that you should not include φ in the answer and that you should not consider Pn,max.b = 12 in.h = 24 in.Clear cover to ties = 1.5 in.Number of longitudinal bars = 6Size of longitudinal bars = No. 9Size of ties = No. 3Concrete strength = 8,500 psiYield strength of longitudinal bars = 60,000 psiYield strength of ties = 40,000 psi

Spiral reinforced columns are less ductile than tied columns, giving spiral columns a lower strength-reduction factor.

_______ columns are those which are not appreciably weakened by moments induced by slenderness effects.

What grade of steel is typically used for longitudinal reinforcement in columns?

The strength reduction factor of compression-controlled spiral columns is _____.

Determine the location of the neutral axis, c, for the following tied column when the largest strain in the concrete is 0.003 and the strain in the tension reinforcement is 0.003.b = 14 in.h = 20 in.Clear cover to ties = 1.5 in.Number of longitudinal bars = 6Size of longitudinal bars = No. 6Size of ties = No. 3Concrete strength = 5,500 psiYield strength of longitudinal bars = 60,000 psiYield strength of ties = 60,000 psi

The minimum number of bars in a _______ column is four.

Determine the required splice length for the uncoated longitudinal bars in the following tied column made of normal-weight concrete. Assume that some of the longitudinal bars are in tension and that the connection should be designed as a Class B contact lap splice. Use ACI 318-14 Table 25.4.2.2 to calculate the development length, and assume that the ties satisfy the Code minimum.Column width, b = 22 in.Column thickness, h = 28 in.Clear cover to ties = 1.5 in.Number of longitudinal bars = 6Size of longitudinal bars = No. 6Size of ties = No. 4Concrete strength = 6,000 psiYield strength of longitudinal bars = 60,000 psiYield strength of ties = 40,000 psi

For tied columns in seismic regions, ties are spaced roughly the width of the column apart.

Reinforced concrete is not elastic and has a compressive strength that is much lower than its tensile strength.