Reading the Charts and Tables
The charts and tables presented in the following pages use the symbols defined here. The load tables (derived in accordance with ACI-318), section properties tables, and diagrams are intended to be read by trained professionals. If you need assistance or additional information, donít hesitate to call us.

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

Strand Designation

  Diameter Aps
3/8" 0.085 in2
7/16" 0.115 in2
1/2" 0.153 in2
1/2" Special 0.167 in2
0.6" 0.217 in2