STEEL REINFORCEMENT 



255 



FIG. 2 



In the nomenclature 

 of reinforced concrete, 

 round, rolled sections 

 are designated as rods; 

 square sections as bars; 

 and rectangular sec- 

 tions, as flats, or flat 

 bars. 



In the table on page 

 253 are given the areas 

 and weights of square 

 and round bars from 

 ft- to 2-in. sizes. 



Bars of Special Con- 

 struction. Some early 

 forms of bars used in 

 reinforcement of con- 

 crete are shown in Fig. 

 1. That shown in (a) 

 is known as the Hyatt 

 bar. An early form 

 of the Thacher bar is 

 shown in (6). In (c) is 

 shown the Staff bar. 

 It consists of a flat bar, 

 through which a coun- 

 tersunk punch has 

 been partly driven, 

 thus forcing the metal 

 out on the opposite 

 side so as to form 

 projections. The De 

 Mann bar is shown in 

 (d). Two forms of the 

 unit bar are shown in 

 (<?) and (f); that in (e) 

 is known as the Siam- 

 ese bar and that at 

 (f) as the quad bar. 



