50 



but x 



d-e 



... 



3.22 3.22 50 



A 5 =.056 de (7) 



Representing the required area of the steel per 12 in. 

 of breadth by ^ s and that of the bar to be used as A, 

 then the spacing of the bars is equal to 



^ (8) 



AS 



It must be remembered, however, that the spacing of 

 the bar must not exceed 2 1 / (d-e). 



In computaing beams as a T section we will consider it 

 safe to have b equal to 1-3 the clear span ; that is, if the 



span is 15 feet, then & 



15x12 



-=6) 



In no case should this exceed the distance between beams. 

 There are three cases to be considered: 



(1) The neutral axis is within the slab. 



(2) The neutral axis is at the bottom of the slab. 



(3) The neutral axis cuts the web. 



CASE I. 



t = slah thlcknpss. 



f distance to neutral axis. 



d total height of beam and slab. 



= width of web. 





