USEFUL DATA 



and girder type of construction. Again, beams serve to deflect hose streams and to 

 form pockets in the ceiling that collect and intensify heat. 



(e) Speed and economy. A flat slab building may be erected in less time and with 

 greater economy than one of the beam and girder type. 



The moment factors used in the design of Corr-Plate Floors, as previously stated, 

 are based on the result of experiment in the laboratory supplemented by tests on 

 actual structures where steel and concrete deformations were measured and stress and 

 moment distribution determined therefrom. The distribution of moment, and sim- 

 ilarly of reinforcement, is given in Fig. 8, where, to avoid confusion, the distribution 

 is given for only one set of reinforcements. The same methods are applied to the rein- 

 forcements at right angles to the ones shown. The figures in the circles are the denomi- 

 nators of the moment coeflBcient per foot width of slab for the band in which they 

 appear; thus the positive moment per foot of width at the center of the band extending 



between columns is, 3f =-rr— and the negative moment over the column for the same 



20 



band is If = 



10 



Similarly for the remaining bands into which the panel is divided. The clear span 



between the column heads in feet, is S, 

 and w is the total dead and live load 

 per square foot of floor. In Fig. 8, the 

 heavy stepped line shows the practical 

 distribution of moment while the dashed 

 curved line shows the actual distribution 

 as determined by experiment. 



The tables on pages 110 and 111 are 

 based on standard Corr-Plate design for 

 stresses of /« = 16,000, /,. = 650; and /a = 

 18,000, /c = 700, respectively, and are for 

 square interior panels. Similar tables are 

 given on pages 112 and 113 to meet the 

 requirements of the Chicago Flat Slab 

 ruling and the Final Report of the Joint 

 Committee. The latter report is given 

 in detail on pages 194 to 211. 



The approximate weight of reinforce- 

 ment per square foot of floor area is 

 given for each span and load and in- 

 cludes steel required for the support of 



T^. ^ ., ^. T • -.^ ^j- the negative moment reinforcement. 



Distribution across Line Y-Y ® 



FiQ. 8 





109 



