62 W. H. WAEREN. 



Moment of Resistance of T Sections. 



-Eft 



-/-^ 





SffT-rSfc 



h-a-x 



i 



i:^,/- - 



•-c 



i 



i 



h-4. 



-±-£a6 



Let P c = the total compressive strength in the concrete 

 „ P c ' = the compressive stress in the stem of the T 

 „ P c " = the compressive stress in the flange of the „ 

 ,, P s = the tensile stress in the steel 

 „ S = the shearing stress in the concrete in pounds per 

 square inch 



a = the sectional area of the steel per inch width of the 

 beam 

 then — ab f s = P c =P a 



ab 



_ Pc _ Ps 



U fs 



Let Sh = the total shear between the rib and flange along 

 their plane of union 

 , , S v = the total vertical shear on the two planes 2-3 and 4-5 



c 

 Assume that S = — and also P, = S h = S v These as- 



8 



sumptions are on the safe side. 



It is clear that for equal strength in shear b should be 

 equal to 2d 



If I = the span of the beam in feet 



&=§ x b x 1 x 12 = ZbSl 



Sr=/f x2dx \ x 12 = QdSl 



h — a 



UK 



c A 



