407 





Experiments on the rupture of steel plates by the contact 

 explosion of loose Tetryl charges have been conducted at the David 

 Taylor Model Basin, and some data obtained therefrom have been kindly 

 supplied to the suthor by ^mbIii* C. H. Gerlach of the Bureau of Ships. 



The comparison of the results of jiq. (61 ) with these data is restricted 

 to the case of single-ply steel plates, the applicability of the theory 

 to laminated plates being uncertain. The value of the energy fraction 

 y , adjusted to bring Eq. (6l) and experimental data into agreement as 

 regards the relation between the charge weight W and the plate thickness 

 a , is used as a criterion of comparison. Using h ^^^ = 0.C932, £ = 

 1,02 kcal/gra,(for loose Tetryl), and £.^ = 0.25, Eq. (61) may be special- 

 ized to 



«^=■'•"<■|v)"('■"^f.■"'*T^)■^ 



(62) 



giving ^ as a function of a /\i-^'^ and a~^. In Eq, (62) and henceforth 

 a^ is expressed in inches, W in pounds, and a~Q in poiinds per square inch. 

 In Table IX are tabulated values of JT along with the experimental values 

 of a and W from lAiich they were calculated. The yield stress o-^ assumed 



for each kind of steel is also tabulated. 



It is seen that the values of JT^ given in Table IX vary from 

 roughly 0,1 to 0.3 in the order of increasing thickness. It might be 



88 



