STEEL REINFORCEMENT 



277 



system, consists of reinforced columns that have a spread cap 

 of heavy reinforcing bars radiating from the column, as 

 illustrated at a, Fig. 8. These rods are held radially by 

 circular reinforcing bars b, to which they are securely wired. 

 By means of this heavy reinforcement, the column is greatly 

 strengthened at the top, and by spreading in this way, it 

 supports a large portion of the floor slab, after the manner 

 of radiating cantilevers. The flat slab that covers the 

 column supports is reinforced in several directions with light 

 reinforcing rods. 



FABRICATED SYSTEMS 



Unit System. The girder frame in the unit system is now 

 made of plain bars, and the stirrups in the latest develop- 

 ment are in the form of an invented U, the construction of 

 the frame being as shown in Fig. 9. 



FIG. 9 



The frame shown in view (a) is fabricated, or fastened 

 together, by a shrinking process; that is, each stirrup and 

 tie-rod is hot-shrunk to the main members. This girder 

 frame is designed to withstand the hard usage of shipment 

 and unloading. The type of frame shown in view (6) is 

 designed for use in districts located so far away from the 

 shops of the manufacturer as to make the freight rates for 

 shipping complete frames prohibitory'. 



In the frames shown in Fig. 9 there are four main rein- 

 forcing rods a, although the frame may be made up with any 



