Change List for this Rule

 

General Order 95

 

Section IV

 

Strength Requirements for All Classes of Lines

48.2     Steel

 

The safety factors specified in Rule 44 shall be applied as follows to structural steel:

 

Tension and Bending: The yield point, 33,000 pounds per square inch, shall be divided by the safety factor to determine the maximum allowable working stress.

 

Compression: The maximum allowable working stress shall be calculated by the following formula:

 

equation

 

Where Smax = maximum allowable working stress, lbs per square inch

 

fs = safety factor specified in Rule 44

 

YP = yield point of the steel, 33,000 lbs. per sq. in.

 

l = unsupported length of member, inches

 

r = radius of gyration of member, inches

 

Shear: The ultimate tensile strength, 60,000 pounds per square inch, shall be multiplied by 2/3 and divided by the safety factor specified in Rule 44 to determine the maximum allowable working stress

 

Where American Society for Testing Materials (ASTM) A36-97 steel is used, the yield point shall be taken as 36,000 pounds per square inch (36ksi) and the tensile strength shall be taken as 58ksi.  If other grades of steel are used, the yield point and ultimate strength used to calculate maximum working stress shall correspond to the minimum values specified in the appropriate ASTM specification for the grade of steel used.

 

Note:      Revised March 30, 1968 by Decision No. 73813 and January 13, 2006 by Decision No. 05-01-030