72 



STEEL OFFICE BUILDINGS. 



TABLE IV. 

 TABLE OF LIVE LOADS, SCHNEIDER'S SPECIFICATIONS. 



CHAP. II. 



"If heavy concentrations, like safes, armatures, or special machinery, are likely to occur on 

 floors, provision should be made for them. For structures carrying traveling machinery, such 

 as cranes, conveyors, etc., 25 per cent shall be added to the stresses resulting from such live load, 

 to provide for the effects of impact and vibration.'-' 



Mr. Schneider's method for live loads is the most rational method yet proposed. In the 

 design of floor slabs when using this method the author has used an equivalent distributed load 

 equal to twice the distributed loads in Table IV, and has omitted the concentrated load and load 

 per lineal foot of girders. 



The floor loads on warehouses and the recommended floor loads per sq. ft. have been tabu- 

 lated by the American Bridge Company in Table V. 



Wind Loads. The wind loads required by different cities are given in Table III. 



Schneider's specifications for wind load are as follows: 



"The wind pressure shall be assumed as acting in any direction horizontally: First. At 20 

 Ib. per sq. ft. on the sides and ends of buildings and on the actually exposed surface, or the vertical 

 projection of roofs; Second. At 30 Ib. per sq. ft. on the total exposed surfaces of all parts com- 

 posing the metal framework. The framework shall be considered an independent structure, 

 without walls, partitions or floors." 



Additional data on wind loads are given in Chapter I. 



Snow Loads. The snow loads on roofs are given in Fig. I, Chapter I. 



Schneider's specifications require "A snow load of 25 Ib. per sq. ft. of horizontal projection 

 of the roof for all slopes up to 20 degrees; this load to be decreased I Ib. for every degree of increase 

 of slope up to 45 degrees, above which no snow load is to be considered. The above snow loads 

 are minimum values for localities, where snow is likely to occur. In severe climates these snow 

 loads should be increased in accordance with the actual conditions existing in these localities." 



