STEEL REINFORCEMENT 273 



cross-section of the construction through the beams 

 or secondary members, of the floor system. Usually, 

 the tiles are from 12 to 16 in. in width and from 6 to 12 in. 

 in depth, the hollow part having the cross-section indicated 

 at a. The tiles are spaced about 5f in. apart, and in the 

 space between them is laid concrete that is reinforced with 

 Kahn bars. The concrete is carried over the top of the tile 

 to a depth of about 2 in. The Kahn bar shown at b in (6) 

 is provided with the usual prongs, or stirrups, which are 

 bent upwards toward the abutments. The tiles c are 

 serrated, or corrugated, along the sides, so as to provide 

 some shearing strength in addition to the adhesion of the 

 concrete. During the construction of this floor system, the 



m 



FIG. 5 



tiles should be held temporarily in position either by placing 

 blocking between them or by nailing them to the forms. 

 It is not customary in this type of construction to use 

 shrinkage rods in the slab that is laid over the top of the tile. 

 Since the tiles are quickly laid on the centering and, con- 

 sequently, minimize the quantity of concrete required for 

 the construction of the floor, and, also, since the concrete 

 placed in conjunction with the tiles sets more rapidly than 

 when placed alone, this particular type of construction can 

 be carried on with considerable rapidity. Such a floor con- 

 struction as this, embodying tile having a hollow air space, 

 acts as a good deadener of sound and also tends to prevent 

 heat from passing from one floor to another. 



