PLASTIC FAILURE OF CYLINDRICAL SHELLS. 



633 



17 



Fig. 25. 



plotted on the surface of the cylinder by the following method. A brass 

 straight-edge was carried for the whole length of the cylinder from the 

 end plates, that straight edge coinciding with each of the axial grid lines 

 in turn. A depth gauge set to a definite reading was moved along the 



straight-edge until its point just 

 touched the distorted cylinder ; the 

 point of contact was marked and gave 

 one position on that contour. The 

 contours were finally drawn in white 

 paint and the cylinder was photo- 

 graphed. The grid was then used 

 to plot the contours on the plane 

 development of the surface, and those 

 contours are shown in a number of the 

 figures to follow. The first tests 

 were made on the incomplete specimen 

 0, the ends of which were supported 

 by wooden disks to which the shell was 

 screwed. The load-displacement curve 

 obtained in Test OA is shown in Fig. 

 25. The test data for this curve are 

 contained in Table III. Thesearegiven 

 as an example of the records kept for each test, but the remainder are 

 not reproduced. 



RAM DISPLACEMENT . INCHES 



Test A on Ctundke 0. 



W.E.P. III 



—2 



