10 



the Gilmore was set for a gage factor of 2. 04. The corrected strain was 

 found by applying a faciend to the indicated strain since 



Srue " R(GF)t^^e 



AR 



'indicated R(GF)set 



e = e ■ / Q^set \ ^ ^ /(-^^ 



corrected indicated \ ^„ j indicated ^ ' 



\ GFtru^ / 



The stresses were then computed using the plane stress relations 



E 



1^' 



o-m - TTTT" Ctm + (^^h) 



_ E 



Since the radial stress is zero at a free boundary, the stress at the 

 boundaries of the cable penetrations were computed using the relation 



cr, = E e 



b 



The pressure effects on the type of gages used in this study have 

 been found to be negligible at the low pressures*^'. To insure that the applied 

 pressure would not effect the indicated strains, compensation gages were 

 placed on blocks of the same material as the shell and the port window, 

 and the gages on these blocks (Fig. 6) were subjected to atmospheric pressure 

 and to the applied external pressure during the test for compensation of the 

 gages on the concave and convex surfaces of the shell, respectively. 



