Change List for this Rule

 

General Order 95

 

Section IV

 

Strength Requirements for All Classes of Lines

48.2 Steel
The required strength of steel structures and components shall be designed using ASCE 10 97 for latticed steel structures and ASCE 48 11 for tubular steel pole structures, as applicable.
Allowable stresses for steel members and their connections shall be derived in conjunction with the safety factors in Rule 44 and the permitted stresses specified in the applicable standard.
Steel members not covered by either of these standards shall be designed using allowable stresses as defined below:
Tension: The maximum allowable tensile stress shall be calculated using the following formula:
Strikeout Equation 48.2
Compression: The maximum allowable compressive stress shall be calculated using the following formula:
Strikeout Equation 48.2
Shear: The maximum allowable shear stress shall be calculated using the following formula:
Strikeout Equation 48.2
Bending: The maximum allowable bending stress for a compact section shall be calculated using the following equation:
Strikeout Equation 48.2
The maximum allowable bending stress for a non-compact section shall be determined according to the provisions of Chapter E of the AISC Manual of Steel Construction, Allowable Stress Design, 9th Edition.
Combined Stresses: The strength of members subjected to combined stresses shall be determined according to the provisions of Chapter H of the AISC Manual of Steel Construction, Allowable Stress Design, 9th Edition.
Where,
Fa = maximum allowable axial stress, psi
Fb = maximum allowable bending stress, psi
Ft = maximum allowable tensile stress, psi
Fv = maximum allowable shear stress, psi
Fy = specified minimum yield stress, psi
Fu = specified minimum tensile stress, psi
SF = safety factor as specified in Rule 44
l = unsupported length of member, inches
r = radius of gyration of member, inches
The values used for specified minimum yield stress, Fy, and specified minimum tensile stress, Fu, shall be the values as listed in the appropriate ASTM specification. If the material specification for the steel is unknown and cannot be determined, the values for Fy and Fu and shall be assumed to be 33,000 psi and 60,000 psi, respectively. The modulus of elasticity, E, is defined to be 29,000 ksi.

 

Note:      Revised March 30, 1968 by Decision No. 73813, January 13, 2006 by Decision No. 05-01-030  and February 5, 2014 by Decision No. 14-02-015.