CAMBRIA STEEL. 103 



TABLES OF SAFE LOADS FOR ANGLES. 



Tables of uniformly distributed safe loads for the usual sizes of 

 angles, are given on pages 138 to 159. In these tables the safe 

 loads for equal leg angles are given on the assumption that one 

 of the legs of the angle is horizontal and the other leg vertical. 

 In the case of angles with unequal legs the safe loads are given 

 for both positions, that is, with the long leg vertical and with the 

 short leg vertical. 



EXAMPLES OF APPLICATION OF TABLES OF 

 SAFE LOADS AND TABLES OF SPACING. 



EXAMPLE I. 



What is the proper size of beam with a clear span ot 24 feet to 

 carry a superimposed load of 30 000 pounds uniformly distributed, 

 the deflection to be such as not to crack a plastered ceiling? 



From the Tables of Safe Loads for Cambria I-Beams,page 111, 

 it is found that a 15-inch standard beam of this length, weighing 

 60 pounds per foot, will carry a gross load of 31 910 pounds, and 

 the weight of the beam itself is 60 X 24 = 1440 pounds. Thus 

 the net load may be 30 470 pounds, so that this is the proper size 

 for the conditions named, as its deflection is within the allowable 

 limit, which is shown to be at a span of 30 feet as indicated by the 

 horizontal line on the table. 



Similarly it may be found from page 112, that a 15-inch special 

 beam, of 60 pounds per foot, will more than suffice, but as this 

 section is not regularly kept in stock the standard 15-inch 60- 

 pound beam should be ordered if prompt delivery is wanted. 



It may also be found from page 114, that an 18-inch 55-pound 

 beam will amply suffice, and as this is both stiffer and lighter than 

 the 15-inch 60-pound beams, it could be used with economy if 

 otherwise suitable for the location. 



EXAMPLE II. 



What is the safe load for an 8-inch standard I-Beam weighing 

 18.0 pounds per foot for a span of 20 feet, the deflection to be such 

 as not to crack a plastered ceiling? 



