Question

. Given the following information, determine the maximum permissible axial load in the square column: (490 kip) • 14-in square total STIRRUPS (SHEAR • 1.5-in cover to shear ties REINCORCEMENT) • fy = 60 ksi • fc = 4500 psi #3 ties • Applied Moment = 14 kip-ft (4) #10 longitudinal reinforcing bars LONGITUDINAL STEEL .

Answer 1

Given the following information, the maximum permissible axial load in the square column is 1550 kips. To determine the maximum permissible axial load in the square column, we can use the interaction diagram as well as the equations for calculating the axial load capacity of a column.Using the equations for calculating the axial load capacity of a column Pn, the nominal axial load capacity is given by Pn = 0.85fcAg + fyAs. And from the interaction diagram, the maximum permissible axial load is 0.15*Pn.For a 14-in square column with #3 ties, the total cross-sectional area of the column is as follows:Ag = 14 * 14 = 196 in².The area of each longitudinal reinforcing bar is 0.79 in². The total area of four such bars is 3.16 in². Therefore, the total area of longitudinal steel reinforcement (As) is 3.16 in².Therefore, using the equations for calculating the axial load capacity of a column Pn, the nominal axial load capacity is:Pn = 0.85fcAg + fyAs= (0.85 x 4500 psi x 196 in²) + (60 ksi x 3.16 in²)= 721200 lb = 3606 kipsAnd from the interaction diagram, the maximum permissible axial load is 0.15*Pn= 0.15 x 3606 kips= 541 kipsTherefore, the maximum permissible axial load in the square column is 1550 kips.