51 



e distance from bottom of beam. 



to center of steel. 

 A s area steel required. 

 f c = compressive value of the concrete 

 f s rr tensile value of steel. 



* 



n *.- 



(2) 

 (3) 



(4) 



Then: 

 x 



"V- h/'+nsr -0 



fc = 



ft 



M 



CASE II. 



Formulae same as Case I, substituting value t for that 

 of x. 



CASE III. 



Generally when the neutral axis falls below the bottom 

 of the slab the compressive value of the concrete between 

 the bottom of the slab and the neutral axis is neglected. 



