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A rectangular beam has a cross section of b = 18 in., h = 22 in., and d = 19.5 in. It is reinforced with three No. 7 Grade 60 bars. The concrete strength is 8,800 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the modulus of rupture of the concrete, fr.

Tied columns are more ductile than spiral columns, giving tied columns a higher strength-reduction factor.

If additional steel reinforcement in a column prevents concrete from expanding outward under compression, then logically it follows that _______.

Over _____ percent of all columns in buildings in nonseismic regions are tied columns.

In tall buildings, the concrete strength in the columns is often selected to be _______ that in the floors.

Ties confine the concrete core and decrease the column’s ductility.

Spiral reinforcement acts to restrain the _______ of the column core under high axial loads.

In tall buildings, concrete strength in the columns is often higher than that in the floors.

What is the strength-reduction factor, φ, for tied columns?

ACI 318-14 Section 25.7.3.1 limits the clear spacing of spirals in a column to a maximum of _______.