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 = 20 in.Clear cover to ties = 1.5 in.Number of longitudinal bars = 6Size of longitudinal bars = No. 6Size of ties = No. 4Concrete strength = 9,000 psiYield strength of longitudinal bars = 60,000 psiYield strength of ties = 60,000 psi

A rectangular beam has a cross section of b = 14 in., h = 26 in., and d = 23.5 in. It is reinforced with two No. 5 Grade 60 bars. The concrete strength is 5,500 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the transformed cross-sectional area of the bars, Ast.

Development length is the longest length of bar in which the bar stress can increase from zero to the yield stress.

Tied columns cannot be L-shaped.

Which of the following sets of items can be used to aid in preventing injury?

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

Use ACI 318-14 Table 25.4.2.2 to determine the development length for the straight tension bars (no hooks) in a rectangular beam with b = 18 in. and d = 24 in., five galvanized No. 9 Grade 60 bars placed in the top of the beam, and No. 3 Grade 60 stirrups located every 6 in. along the span. Assume 5,000-psi lightweight concrete and a clear cover of 1.5 in.

A wall footing has the following conditions. Determine the minimum width of the footing.The bottom of the footing is at a depth of 3 ft below grade.The service dead load is 13 kips/ft, and the service live load is 7 kips/ft.The wall is 14 in. thick.The footing is 16 in. thick.The allowable soil pressure, qa, is 6,000 psf.The soil has a density of 115 lb/ft3.The concrete has a density of 150 lb/ft3.The concrete cover has a thickness of 3 in.f’c = 3,900 psi and fy = 60,000 psi.

Because the designer has little control over the arrangement of the bars in a circular column, the interaction diagram should be computed for the least favorable bar orientation.