| Ac |
Area of core of spirally reinforced compression member measured to outside diameter of spiral |
| Ag |
Gross area of section |
| Aps |
Area of prestressed reinforcement |
| b |
Width of compression face of member |
| f'c |
Specified compressive strength of concrete |
| fpc |
Average compressive stress in concrete due to effective prestress force only |
| fps |
Stress in prestressed reinforcement at nominal strength |
| fpu |
Specified tensile strength of prestressing tendons |
| fse |
Effective stress in prestress reinforcement |
| fy |
Specified yield strength of non-prestressed reinforcement |
| h |
Overall depth of member |
| I |
Moment of inertia of section |
| Mn |
Nominal moment strength at section |
| Mu |
Factored moment at section |
| N |
Design axial load normal to cross section |
| Pn |
Nominal axial load strength at given eccentricity |
| Po |
Nominal axial load strength at zero eccentricity |
| Pu |
Factored axial load at given eccentricity |
| r |
Radius of gyration of cross section |
| Yb |
Distance from bottom fibre to center of gravity of section |
| Z |
Section modulus |
| Zb |
Section modulus with respect to bottom fiber |
| Zt |
Section modulus with respect to top fiber |
| δ |
Moment magnification factor |
| Φ |
Strength reduction factor |
| ρg |
Ratio of total reinforcement area to cross-sectional area of column |
