COLUMNS AND STRUCTURES 263 



beams, girders, and slabs are designed as continuous. Any settle- 

 ment will be bad and generous foundations will prevent settlement. 



The Schneider method calls for expensive foundations, and 

 Mr. Daniel E. Moran suggests using one-half the probable maxi- 

 mum live load, instead of the full live load advised by Mr. Schnei- 

 der. Mr. Moran says: "The maximum probable load is the 

 load which in the opinion of the designer will actually come upon 

 the footings, and is to be determined by a study of the conditions 

 which will obtain when the building is occupied. For instance, 

 in a schoolhouse the number of children in each class room and 

 the weight of desks, chairs, etc., may be determined with con- 

 siderable accuracy and these loads will make the maximum 

 probable live load. As a further illustration, in many school- 

 houses there is an assembly room which is only used when the 

 class rooms are vacant, and consequently if class room loads are 

 used assembly room loads should be omitted or vice versa, the 

 greater one of these loadings to be used for the probable load." 

 See on this point Engineering News, March 6, 1913, and April 

 3, 1913. 



The author was taught, thirty years or more ago, to propor- 

 tion the loads as follows: the dead plus the reduced live loads 

 were carried down and the footing under the corner column carry- 

 ing the least dead load was designed for the dead and live load. 

 The allowable soil pressure was multiplied by the per cent of 

 dead load brought down to this footing, to obtain a "soil factor." 

 The soil factor was divided by the percentage of dead load brought 

 down for each column and thus was obtained a new allowable soil 

 pressure for each column. With these allowable soil pressures 

 as thus determined for each footing the footings were designed 

 for the dead and live load. This method is really practically the 

 same as that proposed by Mr. Schneider, except that the column 

 loaded the most heavily with dead load is the critical column, 

 whereas with the Schneider method the column loaded the most 

 heavily with live load is the critical column. The method so 

 long used by the author is preferred by him, but instead of the 

 corner column carrying the least dead load he selects that 

 column on which the live load is not less than 15 per cent. This 

 will be sufficient for many buildings. When there is much ma- 

 chinery in a building and the building is occupied by large num- 

 bers of employees for eight hours and is closed for sixteen hours 



