620 



PIPPAED AND CHITTY ON EXPERIMENTS ON THE 



Preliminary Tests on Steel and Copper Drums. 



A steel cement drum 20 inches long, 14 inches diameter and 0-028 inch 

 in wall thickness, served for a preliminary check of the test apparatus. 

 The drum was unstiffened except for the support of the bottom and the 

 cover. The load-displacement curve which was obtained as a result of 

 that test indicated that dJBpl a c o m e nt ouive w ltic h wa e o b tained »o a fcw ilt 

 that displacements had been measured before the 



Figs 4. 



' ; ^'■'*' 



2 j* U * '''^e frames at equal spacing 



lM I S i i 



r4-l W,G end-plate 



j'a J'xUgagge angle 



LONGITUDINAL SECTION 



J-^VV 



Tacit weltis at approx 

 2' ctrs, staggeretl 



14 gauge shell 



ij'-1'£ tee ring 



3?*'* i'«' tee-bar stiffeners 

 (•gauge brackeu 



Scale 

 3 



1 Inch = 1 foot 

 t 9 



SECTION XX 



The EXPERIMEKTAL CYLnfDEE. 



strains had fully developed. While the modifications to the rig dictated 

 by that preliminary test were being made, a second drum was tested, but 

 the load was applied by dead weights ; that drum was similar to the first 

 but the wall thickness was 0-032 inch. The load displacement curve is 

 shown in Fig. 7. 



The area under the curve is a measure of the energy absorbed in 

 deforming the cylinder and is 153 inch-lb. In a second test the drum was 

 inverted and a 4-inch-diameter iron ball weighing 7-9 lb. was dropped upon 

 it from a height calculated to give it that amount of energy on impact after 



