48 

 The maximum intensity of stress in compression is J c 



in Ib. per sq. in. 

 The total area of steel required per 12 in. of breadth is 



fc v b 

 The total compression c= - 



The total tension = T=A S .f s 



The total compressive stresses are equal to the total 

 tensile stresses and as the tensile value of the concrete 

 is neglected C=T. 



According to the laws of elasticity the relative deforma- 

 tions on a fiber depend on the distance that fiber is from 

 the neutral avis. Then, representing: the unit elongation 

 of the street in tension by J) 5 and the unit compres- 

 sion of the extreme fiber of the concrete by ) c we gt 



Dc'.x\\D s \ (d-ex) 



Substituting in (2) 



u 2f s . A s (d-e-x) x.J, 

 b.x.Ec E s 



2A S . (d-e-x) 



This equates to ^=1.25^, - - (3) 



