102 CAMBRIA STEEL. 



in which 



W = safe load in pounds for the limit of deflection for plastered 



ceilings = 7 ^ of the span. 

 W s = safe load of tables next above the line giving the limit of 



deflection. 



L = length of span in feet corresponding to W s from the table 

 Li = length of span for the case under consideration. 



This may also be expressed by the following 

 RULE. 



Multiply the safe load next above the heavy line of the tables by 

 the square of the corresponding span in feet and divide the product 

 by the square of the required span. The result will be the required 

 load corresponding to the limit of allowable deflection for plastered 

 ceilings. 



A Table of Deflections for Cambria shapes used as beams, sub- 

 jected to their safe loads uniformly distributed, and accompanying 

 explanations with examples, are given on pages 98 and 99. 



TABLES OF SAFE LOADS FOB I-BEAMS AND CHANNELS. 



Tables of Safe Loads for all sizes and weights of Cambria 

 I-Beams and channels for the usual spans, expressed in feet, are 

 given on pages 106 to 123 inclusive. 



TABLES FOB SPACING OF CAMBRIA I-BEAMS. 



Tables for Spacing of Cambria I-Beams for a total load of 100 

 pounds per square foot including the weight of the beam, corre- 

 sponding to spans from 4 to 48 feet, are given on pages 124 to 135 

 inclusive. 



For any given size of beam the spacing or distances from centers 

 to centers for different intensities of loading varies inversely as 

 the load, so that the spacing for any intensity of loading may be 

 found from the tabular spacing by proportion as stated in the 

 notes at the foot of the tables. 



