310 



PRACTICAL MATHEMATICS 



Example 1. To investigate the distribution of shear stress 

 over the given section. 



FIG, 109, 



(1) For the flange, let 9 be the shear stress at a distance y 

 from the neutral axis. 



T,, -/D \ 1/D 



Then Aw = 



and 



B 



_ [ j,2 \ 



21 U V 



D 



and this relation will only hold for values of ?/ between and 



d D d *Y M\ 



-, when ?/ = , q = 0, and when ?/ = -, q = -y ( D 2 a ^ ). 



2 2 * 81 N / 



(2) For the web let q be the shear stress at a distance y from 

 the neutral axis. 



B 



Then 4, _!(D-a)xl(D+,l) 



and 



