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BELL SYSTEM TECHNICAL JOURNAL 



area, therefore, the pole should be designed to resist only the trans- 

 verse load corresponding to that area. In calculating this load, the 

 wind pressure is considered as acting upon the projected areas of the 

 pole and of the ice-coated wires, strand, etc., for l/2 of each adjacent 

 span. 



Fig. 4 



Fig. 4 shows the relative magnitude of the bending moments at the 

 ground line of a 25-foot pole carrying 10 wires, caused by (a) winds 

 of various velocities with no ice on the wires, and (b) an 8-pound 

 wind with various ice coatings on the wires. In the case of the pole 

 design, it is evident that the wind pressure on the increased "sail 

 area" created by the ice on the wires represents the predominant 

 portion of the storm load. 



